diff --git a/.gitattributes b/.gitattributes
index aa993ad110..0c4ae3d850 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -4,3 +4,4 @@ Cargo.lock  linguist-generated -merge
 vm/src/stdlib/ast/gen.rs    linguist-generated -merge
 Lib/*.py    text working-tree-encoding=UTF-8 eol=LF
 **/*.rs     text working-tree-encoding=UTF-8 eol=LF
+*.pck       binary
diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index ee8d274c18..23f47b574c 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -15,14 +15,19 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CARGO_ARGS: --no-default-features --features stdlib,zlib,importlib,encodings,sqlite,ssl
+  CARGO_ARGS: --no-default-features --features stdlib,importlib,encodings,sqlite,ssl
   # Skip additional tests on Windows. They are checked on Linux and MacOS.
+  # test_glob: many failing tests
+  # test_io: many failing tests
+  # test_os: many failing tests
+  # test_pathlib: support.rmtree() failing
+  # test_posixpath: OSError: (22, 'The filename, directory name, or volume label syntax is incorrect. (os error 123)')
+  # test_venv: couple of failing tests
   WINDOWS_SKIPS: >-
-    test_datetime
     test_glob
-    test_importlib
     test_io
     test_os
+    test_rlcompleter
     test_pathlib
     test_posixpath
     test_venv
@@ -34,7 +39,7 @@ env:
   # PLATFORM_INDEPENDENT_TESTS are tests that do not depend on the underlying OS. They are currently
   # only run on Linux to speed up the CI.
   PLATFORM_INDEPENDENT_TESTS: >-
-    test_argparse
+    test__colorize
     test_array
     test_asyncgen
     test_binop
@@ -59,7 +64,6 @@ env:
     test_dis
     test_enumerate
     test_exception_variations
-    test_exceptions
     test_float
     test_format
     test_fractions
@@ -100,12 +104,11 @@ env:
     test_tuple
     test_types
     test_unary
-    test_unicode
     test_unpack
     test_weakref
     test_yield_from
   # Python version targeted by the CI.
-  PYTHON_VERSION: "3.12.3"
+  PYTHON_VERSION: "3.13.1"
 
 jobs:
   rust_tests:
@@ -378,7 +381,8 @@ jobs:
         with: { wabt-version: "1.0.30" }
       - name: check wasm32-unknown without js
         run: |
-          cargo build --release --manifest-path wasm/wasm-unknown-test/Cargo.toml --target wasm32-unknown-unknown --verbose
+          cd wasm/wasm-unknown-test
+          cargo build --release --verbose
           if wasm-objdump -xj Import target/wasm32-unknown-unknown/release/wasm_unknown_test.wasm; then
             echo "ERROR: wasm32-unknown module expects imports from the host environment" >2
           fi
diff --git a/.github/workflows/cron-ci.yaml b/.github/workflows/cron-ci.yaml
index 0880e2d249..4b8e701ced 100644
--- a/.github/workflows/cron-ci.yaml
+++ b/.github/workflows/cron-ci.yaml
@@ -6,8 +6,8 @@ on:
 name: Periodic checks/tasks
 
 env:
-  CARGO_ARGS: --no-default-features --features stdlib,zlib,importlib,encodings,ssl,jit
-  PYTHON_VERSION: "3.12.0"
+  CARGO_ARGS: --no-default-features --features stdlib,importlib,encodings,ssl,jit
+  PYTHON_VERSION: "3.13.1"
 
 jobs:
   # codecov collects code coverage data from the rust tests, python snippets and python test suite.
@@ -24,7 +24,7 @@ jobs:
           python-version: ${{ env.PYTHON_VERSION }}
       - run: sudo apt-get update && sudo apt-get -y install lcov
       - name: Run cargo-llvm-cov with Rust tests.
-        run: cargo llvm-cov --no-report --workspace --exclude rustpython_wasm --verbose --no-default-features --features stdlib,zlib,importlib,encodings,ssl,jit
+        run: cargo llvm-cov --no-report --workspace --exclude rustpython_wasm --verbose --no-default-features --features stdlib,importlib,encodings,ssl,jit
       - name: Run cargo-llvm-cov with Python snippets.
         run: python scripts/cargo-llvm-cov.py
         continue-on-error: true
@@ -97,6 +97,9 @@ jobs:
           cd website
           [ -f ./_data/whats_left.temp ] && cp ./_data/whats_left.temp ./_data/whats_left_lastrun.temp
           cp ../whats_left.temp ./_data/whats_left.temp
+          rm _data/whats_left/modules.csv
+          cat _data/whats_left.temp | grep "(entire module)" | cut -d ' ' -f 1 | sort >> ../_data/whats_left/modules.csv
+
           git add -A
           if git -c user.name="Github Actions" -c user.email="actions@github.com" commit -m "Update what is left results" --author="$GITHUB_ACTOR"; then
             git push
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 5554ed0a8b..99035d04fc 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -16,7 +16,7 @@ permissions:
   contents: write
 
 env:
-  CARGO_ARGS: --no-default-features --features stdlib,zlib,importlib,encodings,sqlite,ssl
+  CARGO_ARGS: --no-default-features --features stdlib,importlib,encodings,sqlite,ssl
 
 jobs:
   build:
diff --git a/Cargo.lock b/Cargo.lock
index 5d5db7f5ca..67e0813b7b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,12 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
-
-[[package]]
-name = "Inflector"
-version = "0.11.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fe438c63458706e03479442743baae6c88256498e6431708f6dfc520a26515d3"
+version = 4
 
 [[package]]
 name = "adler2"
@@ -27,10 +21,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e89da841a80418a9b391ebaea17f5c112ffaaa96f621d2c285b5174da76b9011"
 dependencies = [
  "cfg-if",
- "getrandom",
+ "getrandom 0.2.15",
  "once_cell",
  "version_check",
- "zerocopy",
+ "zerocopy 0.7.35",
 ]
 
 [[package]]
@@ -68,9 +62,9 @@ dependencies = [
 
 [[package]]
 name = "anyhow"
-version = "1.0.89"
+version = "1.0.95"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "86fdf8605db99b54d3cd748a44c6d04df638eb5dafb219b135d0149bd0db01f6"
+checksum = "34ac096ce696dc2fcabef30516bb13c0a68a11d30131d3df6f04711467681b04"
 
 [[package]]
 name = "approx"
@@ -115,9 +109,9 @@ dependencies = [
 
 [[package]]
 name = "autocfg"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0c4b4d0bd25bd0b74681c0ad21497610ce1b7c91b1022cd21c80c6fbdd9476b0"
+checksum = "ace50bade8e6234aa140d9a2f552bbee1db4d353f69b8217bc503490fc1a9f26"
 
 [[package]]
 name = "base64"
@@ -133,9 +127,9 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bitflags"
-version = "2.6.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
+checksum = "8f68f53c83ab957f72c32642f3868eec03eb974d1fb82e453128456482613d36"
 
 [[package]]
 name = "blake2"
@@ -157,9 +151,9 @@ dependencies = [
 
 [[package]]
 name = "bstr"
-version = "1.10.0"
+version = "1.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "40723b8fb387abc38f4f4a37c09073622e41dd12327033091ef8950659e6dc0c"
+checksum = "531a9155a481e2ee699d4f98f43c0ca4ff8ee1bfd55c31e9e98fb29d2b176fe0"
 dependencies = [
  "memchr",
  "regex-automata",
@@ -168,15 +162,15 @@ dependencies = [
 
 [[package]]
 name = "bumpalo"
-version = "3.16.0"
+version = "3.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "79296716171880943b8470b5f8d03aa55eb2e645a4874bdbb28adb49162e012c"
+checksum = "1628fb46dfa0b37568d12e5edd512553eccf6a22a78e8bde00bb4aed84d5bdbf"
 
 [[package]]
 name = "bytemuck"
-version = "1.18.0"
+version = "1.21.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "94bbb0ad554ad961ddc5da507a12a29b14e4ae5bda06b19f575a3e6079d2e2ae"
+checksum = "ef657dfab802224e671f5818e9a4935f9b1957ed18e58292690cc39e7a4092a3"
 
 [[package]]
 name = "byteorder"
@@ -196,9 +190,9 @@ dependencies = [
 
 [[package]]
 name = "bzip2-sys"
-version = "0.1.11+1.0.8"
+version = "0.1.12+1.0.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "736a955f3fa7875102d57c82b8cac37ec45224a07fd32d58f9f7a186b6cd4cdc"
+checksum = "72ebc2f1a417f01e1da30ef264ee86ae31d2dcd2d603ea283d3c244a883ca2a9"
 dependencies = [
  "cc",
  "libc",
@@ -222,9 +216,9 @@ checksum = "37b2a672a2cb129a2e41c10b1224bb368f9f37a2b16b612598138befd7b37eb5"
 
 [[package]]
 name = "cc"
-version = "1.1.21"
+version = "1.2.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07b1695e2c7e8fc85310cde85aeaab7e3097f593c91d209d3f9df76c928100f0"
+checksum = "0c3d1b2e905a3a7b00a6141adb0e4c0bb941d11caf55349d863942a1cc44e3c9"
 dependencies = [
  "shlex",
 ]
@@ -235,12 +229,6 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
-[[package]]
-name = "cfg_aliases"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fd16c4719339c4530435d38e511904438d07cce7950afa3718a84ac36c10e89e"
-
 [[package]]
 name = "cfg_aliases"
 version = "0.2.1"
@@ -249,9 +237,9 @@ checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
 [[package]]
 name = "chrono"
-version = "0.4.38"
+version = "0.4.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a21f936df1771bf62b77f047b726c4625ff2e8aa607c01ec06e5a05bd8463401"
+checksum = "7e36cc9d416881d2e24f9a963be5fb1cd90966419ac844274161d10488b3e825"
 dependencies = [
  "android-tzdata",
  "iana-time-zone",
@@ -272,7 +260,7 @@ dependencies = [
  "bitflags 1.3.2",
  "strsim",
  "textwrap 0.11.0",
- "unicode-width",
+ "unicode-width 0.1.14",
  "vec_map",
 ]
 
@@ -287,14 +275,14 @@ dependencies = [
 
 [[package]]
 name = "console"
-version = "0.15.8"
+version = "0.15.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0e1f83fc076bd6dd27517eacdf25fef6c4dfe5f1d7448bafaaf3a26f13b5e4eb"
+checksum = "ea3c6ecd8059b57859df5c69830340ed3c41d30e3da0c1cbed90a96ac853041b"
 dependencies = [
  "encode_unicode",
- "lazy_static 1.5.0",
  "libc",
- "windows-sys 0.52.0",
+ "once_cell",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -307,12 +295,6 @@ dependencies = [
  "wasm-bindgen",
 ]
 
-[[package]]
-name = "convert_case"
-version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6245d59a3e82a7fc217c5828a6692dbc6dfb63a0c8c90495621f7b9d79704a0e"
-
 [[package]]
 name = "core-foundation"
 version = "0.9.4"
@@ -331,9 +313,9 @@ checksum = "773648b94d0e5d620f64f280777445740e61fe701025087ec8b57f45c791888b"
 
 [[package]]
 name = "cpufeatures"
-version = "0.2.14"
+version = "0.2.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "608697df725056feaccfa42cffdaeeec3fccc4ffc38358ecd19b243e716a78e0"
+checksum = "59ed5838eebb26a2bb2e58f6d5b5316989ae9d08bab10e0e6d103e656d1b0280"
 dependencies = [
  "libc",
 ]
@@ -501,9 +483,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-deque"
-version = "0.8.5"
+version = "0.8.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "613f8cc01fe9cf1a3eb3d7f488fd2fa8388403e97039e2f73692932e291a770d"
+checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
 dependencies = [
  "crossbeam-epoch",
  "crossbeam-utils",
@@ -520,15 +502,15 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-utils"
-version = "0.8.20"
+version = "0.8.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "22ec99545bb0ed0ea7bb9b8e1e9122ea386ff8a48c0922e43f36d45ab09e0e80"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
 
 [[package]]
 name = "crunchy"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a81dae078cea95a014a339291cec439d2f232ebe854a9d672b796c6afafa9b7"
+checksum = "43da5946c66ffcc7745f48db692ffbb10a83bfe0afd96235c5c2a4fb23994929"
 
 [[package]]
 name = "crypto-common"
@@ -542,9 +524,9 @@ dependencies = [
 
 [[package]]
 name = "csv"
-version = "1.3.0"
+version = "1.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ac574ff4d437a7b5ad237ef331c17ccca63c46479e5b5453eb8e10bb99a759fe"
+checksum = "acdc4883a9c96732e4733212c01447ebd805833b7275a73ca3ee080fd77afdaf"
 dependencies = [
  "csv-core",
  "itoa",
@@ -554,24 +536,32 @@ dependencies = [
 
 [[package]]
 name = "csv-core"
-version = "0.1.11"
+version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5efa2b3d7902f4b634a20cae3c9c4e6209dc4779feb6863329607560143efa70"
+checksum = "7d02f3b0da4c6504f86e9cd789d8dbafab48c2321be74e9987593de5a894d93d"
 dependencies = [
  "memchr",
 ]
 
 [[package]]
 name = "derive_more"
-version = "0.99.18"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5f33878137e4dafd7fa914ad4e259e18a4e8e532b9617a2d0150262bf53abfce"
+checksum = "4a9b99b9cbbe49445b21764dc0625032a89b145a2642e67603e1c936f5458d05"
+dependencies = [
+ "derive_more-impl",
+]
+
+[[package]]
+name = "derive_more-impl"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb7330aeadfbe296029522e6c40f315320aba36fc43a5b3632f3795348f3bd22"
 dependencies = [
- "convert_case",
  "proc-macro2",
  "quote",
- "rustc_version",
- "syn 2.0.77",
+ "syn 2.0.98",
+ "unicode-xid",
 ]
 
 [[package]]
@@ -620,9 +610,9 @@ dependencies = [
 
 [[package]]
 name = "dyn-clone"
-version = "1.0.17"
+version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0d6ef0072f8a535281e4876be788938b528e9a1d43900b82c2569af7da799125"
+checksum = "feeef44e73baff3a26d371801df019877a9866a8c493d315ab00177843314f35"
 
 [[package]]
 name = "either"
@@ -632,9 +622,9 @@ checksum = "60b1af1c220855b6ceac025d3f6ecdd2b7c4894bfe9cd9bda4fbb4bc7c0d4cf0"
 
 [[package]]
 name = "encode_unicode"
-version = "0.3.6"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
+checksum = "34aa73646ffb006b8f5147f3dc182bd4bcb190227ce861fc4a4844bf8e3cb2c0"
 
 [[package]]
 name = "endian-type"
@@ -655,18 +645,18 @@ dependencies = [
 
 [[package]]
 name = "equivalent"
-version = "1.0.1"
+version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
 
 [[package]]
 name = "errno"
-version = "0.3.9"
+version = "0.3.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "534c5cf6194dfab3db3242765c03bbe257cf92f22b38f6bc0c58d59108a820ba"
+checksum = "33d852cb9b869c2a9b3df2f71a3074817f01e1844f839a144f5fcef059a4eb5d"
 dependencies = [
  "libc",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -730,12 +720,12 @@ dependencies = [
 
 [[package]]
 name = "flate2"
-version = "1.0.33"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "324a1be68054ef05ad64b861cc9eaf1d623d2d8cb25b4bf2cb9cdd902b4bf253"
+checksum = "11faaf5a5236997af9848be0bef4db95824b1d534ebc64d0f0c6cf3e67bd38dc"
 dependencies = [
  "crc32fast",
- "libz-sys",
+ "libz-rs-sys",
  "miniz_oxide",
 ]
 
@@ -781,12 +771,12 @@ dependencies = [
 
 [[package]]
 name = "gethostname"
-version = "0.2.3"
+version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c1ebd34e35c46e00bb73e81363248d627782724609fe1b6396f553f68fe3862e"
+checksum = "4fd4b8790c0792e3b11895efdf5f289ebe8b59107a6624f1cce68f24ff8c7035"
 dependencies = [
- "libc",
- "winapi",
+ "rustix",
+ "windows-targets 0.52.6",
 ]
 
 [[package]]
@@ -795,7 +785,7 @@ version = "0.2.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14dbbfd5c71d70241ecf9e6f13737f7b5ce823821063188d7e46c41d371eebd5"
 dependencies = [
- "unicode-width",
+ "unicode-width 0.1.14",
 ]
 
 [[package]]
@@ -807,15 +797,29 @@ dependencies = [
  "cfg-if",
  "js-sys",
  "libc",
- "wasi",
+ "wasi 0.11.0+wasi-snapshot-preview1",
  "wasm-bindgen",
 ]
 
 [[package]]
-name = "glob"
+name = "getrandom"
 version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+checksum = "43a49c392881ce6d5c3b8cb70f98717b7c07aabbdff06687b9030dbfbe2725f8"
+dependencies = [
+ "cfg-if",
+ "js-sys",
+ "libc",
+ "wasi 0.13.3+wasi-0.2.2",
+ "wasm-bindgen",
+ "windows-targets 0.52.6",
+]
+
+[[package]]
+name = "glob"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8d1add55171497b4705a648c6b583acafb01d58050a51727785f0b2c8e0a2b2"
 
 [[package]]
 name = "half"
@@ -842,6 +846,12 @@ dependencies = [
  "ahash",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.15.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bf151400ff0baff5465007dd2f3e717f3fe502074ca563069ce3a6629d07b289"
+
 [[package]]
 name = "heck"
 version = "0.5.0"
@@ -877,11 +887,11 @@ checksum = "dfa686283ad6dd069f105e5ab091b04c62850d3e4cf5d67debad1933f55023df"
 
 [[package]]
 name = "home"
-version = "0.5.9"
+version = "0.5.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3d1354bf6b7235cb4a0576c2619fd4ed18183f689b12b006a0ee7329eeff9a5"
+checksum = "589533453244b0995c858700322199b2becb13b627df2851f64a2775d024abcf"
 dependencies = [
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -909,12 +919,12 @@ dependencies = [
 
 [[package]]
 name = "indexmap"
-version = "2.5.0"
+version = "2.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "68b900aa2f7301e21c36462b170ee99994de34dff39a4a6a528e80e7376d07e5"
+checksum = "8c9c992b02b5b4c94ea26e32fe5bccb7aa7d9f390ab5c1221ff895bc7ea8b652"
 dependencies = [
  "equivalent",
- "hashbrown",
+ "hashbrown 0.15.2",
 ]
 
 [[package]]
@@ -925,26 +935,27 @@ checksum = "b248f5224d1d606005e02c97f5aa4e88eeb230488bcc03bc9ca4d7991399f2b5"
 
 [[package]]
 name = "insta"
-version = "1.40.0"
+version = "1.42.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6593a41c7a73841868772495db7dc1e8ecab43bb5c0b6da2059246c4b506ab60"
+checksum = "71c1b125e30d93896b365e156c33dadfffab45ee8400afcbba4752f59de08a86"
 dependencies = [
  "console",
- "lazy_static 1.5.0",
  "linked-hash-map",
+ "once_cell",
+ "pin-project",
  "similar",
 ]
 
 [[package]]
 name = "is-macro"
-version = "0.3.6"
+version = "0.3.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2069faacbe981460232f880d26bf3c7634e322d49053aa48c27e3ae642f728f1"
+checksum = "1d57a3e447e24c22647738e4607f1df1e0ec6f72e16182c4cd199f647cdfb0e4"
 dependencies = [
- "Inflector",
+ "heck",
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -965,18 +976,28 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b192c782037fadd9cfa75548310488aabdbf3d2da73885b31bd0abd03351285"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "itoa"
-version = "1.0.11"
+version = "1.0.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "49f1f14873335454500d59611f1cf4a4b0f786f9ac11f4312a78e4cf2566695b"
+checksum = "d75a2a4b1b190afb6f5425f10f6a8f959d2ea0b9c2b1d79553551850539e4674"
 
 [[package]]
 name = "js-sys"
-version = "0.3.70"
+version = "0.3.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1868808506b929d7b0cfa8f75951347aa71bb21144b7791bae35d9bccfcfe37a"
+checksum = "1cfaf33c695fc6e08064efbc1f72ec937429614f25eef83af942d0e227c3a28f"
 dependencies = [
+ "once_cell",
  "wasm-bindgen",
 ]
 
@@ -1005,6 +1026,12 @@ version = "0.20.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "507460a910eb7b32ee961886ff48539633b788a36b65692b95f225b844c82553"
 
+[[package]]
+name = "lambert_w"
+version = "1.0.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45bf98425154bfe790a47b72ac452914f6df9ebfb202bc59e089e29db00258cf"
+
 [[package]]
 name = "lazy_static"
 version = "0.2.11"
@@ -1049,9 +1076,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.159"
+version = "0.2.169"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "561d97a539a36e26a9a5fad1ea11a3039a67714694aaa379433e580854bc3dc5"
+checksum = "b5aba8db14291edd000dfcc4d620c7ebfb122c613afb886ca8803fa4e128a20a"
 
 [[package]]
 name = "libffi"
@@ -1072,11 +1099,21 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "libloading"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc2f4eb4bc735547cfed7c0a4922cbd04a4655978c09b54f1f7b228750664c34"
+dependencies = [
+ "cfg-if",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "libm"
-version = "0.2.8"
+version = "0.2.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4ec2a862134d2a7d32d7983ddcdd1c4923530833c9f2ea1a44fc5fa473989058"
+checksum = "8355be11b20d696c8f18f6cc018c4e372165b1fa8126cef092399c9951984ffa"
 
 [[package]]
 name = "libredox"
@@ -1084,7 +1121,7 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "libc",
 ]
 
@@ -1100,14 +1137,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "libz-sys"
-version = "1.1.20"
+name = "libz-rs-sys"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2d16453e800a8cf6dd2fc3eb4bc99b786a9b90c663b8559a5b1a041bf89e472"
+checksum = "902bc563b5d65ad9bba616b490842ef0651066a1a1dc3ce1087113ffcb873c8d"
 dependencies = [
- "cc",
- "pkg-config",
- "vcpkg",
+ "zlib-rs",
 ]
 
 [[package]]
@@ -1118,9 +1153,9 @@ checksum = "0717cef1bc8b636c6e1c1bbdefc09e6322da8a9321966e8928ef80d20f7f770f"
 
 [[package]]
 name = "linux-raw-sys"
-version = "0.4.14"
+version = "0.4.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "78b3ae25bc7c8c38cec158d1f2757ee79e9b3740fbc7ccf0e59e4b08d793fa89"
+checksum = "d26c52dbd32dccf2d10cac7725f8eae5296885fb5703b261f7d0a0739ec807ab"
 
 [[package]]
 name = "lock_api"
@@ -1134,9 +1169,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.22"
+version = "0.4.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+checksum = "04cbf5b083de1c7e0222a7a51dbfdba1cbe1c6ab0b15e29fff3f6c077fd9cd9f"
 
 [[package]]
 name = "lz4_flex"
@@ -1149,11 +1184,11 @@ dependencies = [
 
 [[package]]
 name = "mac_address"
-version = "1.1.7"
+version = "1.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8836fae9d0d4be2c8b4efcdd79e828a2faa058a90d005abf42f91cac5493a08e"
+checksum = "c0aeb26bf5e836cc1c341c8106051b573f1766dfa05aa87f0b98be5e51b02303"
 dependencies = [
- "nix 0.28.0",
+ "nix",
  "winapi",
 ]
 
@@ -1168,9 +1203,9 @@ dependencies = [
 
 [[package]]
 name = "malachite"
-version = "0.4.16"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5616515d632967cd329b6f6db96be9a03ea0b3a49cdbc45b0016803dad8a77b7"
+checksum = "2fbdf9cb251732db30a7200ebb6ae5d22fe8e11397364416617d2c2cf0c51cb5"
 dependencies = [
  "malachite-base",
  "malachite-nz",
@@ -1179,11 +1214,11 @@ dependencies = [
 
 [[package]]
 name = "malachite-base"
-version = "0.4.16"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "46059721011b0458b7bd6d9179be5d0b60294281c23320c207adceaecc54d13b"
+checksum = "5ea0ed76adf7defc1a92240b5c36d5368cfe9251640dcce5bd2d0b7c1fd87aeb"
 dependencies = [
- "hashbrown",
+ "hashbrown 0.14.5",
  "itertools 0.11.0",
  "libm",
  "ryu",
@@ -1191,9 +1226,9 @@ dependencies = [
 
 [[package]]
 name = "malachite-bigint"
-version = "0.2.0"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "17703a19c80bbdd0b7919f0f104f3b0597f7de4fc4e90a477c15366a5ba03faa"
+checksum = "d149aaa2965d70381709d9df4c7ee1fc0de1c614a4efc2ee356f5e43d68749f8"
 dependencies = [
  "derive_more",
  "malachite",
@@ -1204,9 +1239,9 @@ dependencies = [
 
 [[package]]
 name = "malachite-nz"
-version = "0.4.16"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1503b27e825cabd1c3d0ff1e95a39fb2ec9eab6fd3da6cfa41aec7091d273e78"
+checksum = "34a79feebb2bc9aa7762047c8e5495269a367da6b5a90a99882a0aeeac1841f7"
 dependencies = [
  "itertools 0.11.0",
  "libm",
@@ -1215,9 +1250,9 @@ dependencies = [
 
 [[package]]
 name = "malachite-q"
-version = "0.4.16"
+version = "0.4.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a475503a70a3679dbe3b9b230a23622516742528ba614a7b2490f180ea9cb514"
+checksum = "50f235d5747b1256b47620f5640c2a17a88c7569eebdf27cd9cb130e1a619191"
 dependencies = [
  "itertools 0.11.0",
  "malachite-base",
@@ -1272,20 +1307,20 @@ dependencies = [
 
 [[package]]
 name = "miniz_oxide"
-version = "0.8.0"
+version = "0.8.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2d80299ef12ff69b16a84bb182e3b9df68b5a91574d3d4fa6e41b65deec4df1"
+checksum = "b3b1c9bd4fe1f0f8b387f6eb9eb3b4a1aa26185e5750efb9140301703f62cd1b"
 dependencies = [
  "adler2",
 ]
 
 [[package]]
 name = "mt19937"
-version = "2.0.1"
+version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12ca7f22ed370d5991a9caec16a83187e865bc8a532f889670337d5a5689e3a1"
+checksum = "df7151a832e54d2d6b2c827a20e5bcdd80359281cd2c354e725d4b82e7c471de"
 dependencies = [
- "rand_core",
+ "rand_core 0.9.1",
 ]
 
 [[package]]
@@ -1297,28 +1332,15 @@ dependencies = [
  "smallvec",
 ]
 
-[[package]]
-name = "nix"
-version = "0.28.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab2156c4fce2f8df6c499cc1c763e4394b7482525bf2a9701c9d79d215f519e4"
-dependencies = [
- "bitflags 2.6.0",
- "cfg-if",
- "cfg_aliases 0.1.1",
- "libc",
- "memoffset",
-]
-
 [[package]]
 name = "nix"
 version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71e2746dc3a24dd78b3cfcb7be93368c6de9963d30f43a6a73998a9cf4b17b46"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
- "cfg_aliases 0.2.1",
+ "cfg_aliases",
  "libc",
  "memoffset",
 ]
@@ -1377,14 +1399,14 @@ checksum = "af1844ef2428cc3e1cb900be36181049ef3d3193c63e43026cfe202983b27a56"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "once_cell"
-version = "1.19.0"
+version = "1.20.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3fdb12b2476b595f9358c5161aa467c2438859caa136dec86c26fdd2efe17b92"
+checksum = "945462a4b81e43c4e3ba96bd7b49d834c6f61198356aa858733bc4acf3cbe62e"
 
 [[package]]
 name = "oorandom"
@@ -1394,11 +1416,11 @@ checksum = "b410bbe7e14ab526a0e86877eb47c6996a2bd7746f027ba551028c925390e4e9"
 
 [[package]]
 name = "openssl"
-version = "0.10.66"
+version = "0.10.71"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9529f4786b70a3e8c61e11179af17ab6188ad8d0ded78c5529441ed39d4bd9c1"
+checksum = "5e14130c6a98cd258fdcb0fb6d744152343ff729cbfcb28c656a9d12b999fbcd"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
  "foreign-types",
  "libc",
@@ -1415,29 +1437,29 @@ checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "openssl-probe"
-version = "0.1.5"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ff011a302c396a5197692431fc1948019154afc178baf7d8e37367442a4601cf"
+checksum = "d05e27ee213611ffe7d6348b942e8f942b37114c00cc03cec254295a4a17852e"
 
 [[package]]
 name = "openssl-src"
-version = "300.3.2+3.3.2"
+version = "300.4.2+3.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a211a18d945ef7e648cc6e0058f4c548ee46aab922ea203e0d30e966ea23647b"
+checksum = "168ce4e058f975fe43e89d9ccf78ca668601887ae736090aacc23ae353c298e2"
 dependencies = [
  "cc",
 ]
 
 [[package]]
 name = "openssl-sys"
-version = "0.9.103"
+version = "0.9.106"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f9e8deee91df40a943c71b917e5874b951d32a802526c85721ce3b776c929d6"
+checksum = "8bb61ea9811cc39e3c2069f40b8b8e2e70d8569b361f879786cc7ed48b777cdd"
 dependencies = [
  "cc",
  "libc",
@@ -1454,9 +1476,9 @@ checksum = "978aa494585d3ca4ad74929863093e87cac9790d81fe7aba2b3dc2890643a0fc"
 
 [[package]]
 name = "page_size"
-version = "0.4.2"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "eebde548fbbf1ea81a99b128872779c437752fb99f217c45245e1a61dcd9edcd"
+checksum = "30d5b2194ed13191c1999ae0704b7839fb18384fa22e49b57eeaa97d79ce40da"
 dependencies = [
  "libc",
  "winapi",
@@ -1480,7 +1502,7 @@ checksum = "1e401f977ab385c9e4e3ab30627d6f26d00e2c73eef317493c4ec6d468726cf8"
 dependencies = [
  "cfg-if",
  "libc",
- "redox_syscall 0.5.5",
+ "redox_syscall 0.5.8",
  "smallvec",
  "windows-targets 0.52.6",
 ]
@@ -1493,18 +1515,18 @@ checksum = "57c0d7b74b563b49d38dae00a0c37d4d6de9b432382b2892f0574ddcae73fd0a"
 
 [[package]]
 name = "phf"
-version = "0.11.2"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ade2d8b8f33c7333b51bcf0428d37e217e9f32192ae4772156f65063b8ce03dc"
+checksum = "1fd6780a80ae0c52cc120a26a1a42c1ae51b247a253e4e06113d23d2c2edd078"
 dependencies = [
  "phf_shared",
 ]
 
 [[package]]
 name = "phf_codegen"
-version = "0.11.2"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8d39688d359e6b34654d328e262234662d16cc0f60ec8dcbe5e718709342a5a"
+checksum = "aef8048c789fa5e851558d709946d6d79a8ff88c0440c587967f8e94bfb1216a"
 dependencies = [
  "phf_generator",
  "phf_shared",
@@ -1512,21 +1534,41 @@ dependencies = [
 
 [[package]]
 name = "phf_generator"
-version = "0.11.2"
+version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "48e4cc64c2ad9ebe670cb8fd69dd50ae301650392e81c05f9bfcb2d5bdbc24b0"
+checksum = "3c80231409c20246a13fddb31776fb942c38553c51e871f8cbd687a4cfb5843d"
 dependencies = [
  "phf_shared",
- "rand",
+ "rand 0.8.5",
 ]
 
 [[package]]
 name = "phf_shared"
-version = "0.11.2"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67eabc2ef2a60eb7faa00097bd1ffdb5bd28e62bf39990626a582201b7a754e5"
+dependencies = [
+ "siphasher 1.0.1",
+]
+
+[[package]]
+name = "pin-project"
+version = "1.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "90fcb95eef784c2ac79119d1dd819e162b5da872ce6f3c3abe1e8ca1c082f72b"
+checksum = "dfe2e71e1471fe07709406bf725f710b02927c9c54b2b5b2ec0e8087d97c327d"
 dependencies = [
- "siphasher",
+ "pin-project-internal",
+]
+
+[[package]]
+name = "pin-project-internal"
+version = "1.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f6e859e6e5bd50440ab63c47e3ebabc90f26251f7c73c3d3e837b74a1cc3fa67"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -1571,14 +1613,14 @@ checksum = "52a40bc70c2c58040d2d8b167ba9a5ff59fc9dab7ad44771cfde3dcfde7a09c6"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "portable-atomic"
-version = "1.8.0"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d30538d42559de6b034bc76fd6dd4c38961b1ee5c6c56e3808c50128fdbc22ce"
+checksum = "280dc24453071f1b63954171985a0b0d30058d287960968b9b2aca264c8d4ee6"
 
 [[package]]
 name = "ppv-lite86"
@@ -1586,29 +1628,33 @@ version = "0.2.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "77957b295656769bb8ad2b6a6b09d897d94f05c41b069aede1fcdaa675eaea04"
 dependencies = [
- "zerocopy",
+ "zerocopy 0.7.35",
 ]
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.86"
+version = "1.0.93"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+checksum = "60946a68e5f9d28b0dc1c21bb8a97ee7d018a8b322fa57838ba31cc878e22d99"
 dependencies = [
  "unicode-ident",
 ]
 
 [[package]]
 name = "puruspe"
-version = "0.2.5"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3804877ffeba468c806c2ad9057bbbae92e4b2c410c2f108baaa0042f241fa4c"
+checksum = "d76c522e44709f541a403db419a7e34d6fbbc8e6b208589ae29a030cddeefd96"
+dependencies = [
+ "lambert_w",
+ "num-complex",
+]
 
 [[package]]
 name = "pyo3"
-version = "0.22.4"
+version = "0.22.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "00e89ce2565d6044ca31a3eb79a334c3a79a841120a98f64eea9f579564cb691"
+checksum = "f402062616ab18202ae8319da13fa4279883a2b8a9d9f83f20dbade813ce1884"
 dependencies = [
  "cfg-if",
  "indoc",
@@ -1624,9 +1670,9 @@ dependencies = [
 
 [[package]]
 name = "pyo3-build-config"
-version = "0.22.4"
+version = "0.22.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d8afbaf3abd7325e08f35ffb8deb5892046fcb2608b703db6a583a5ba4cea01e"
+checksum = "b14b5775b5ff446dd1056212d778012cbe8a0fbffd368029fd9e25b514479c38"
 dependencies = [
  "once_cell",
  "target-lexicon",
@@ -1634,9 +1680,9 @@ dependencies = [
 
 [[package]]
 name = "pyo3-ffi"
-version = "0.22.4"
+version = "0.22.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ec15a5ba277339d04763f4c23d85987a5b08cbb494860be141e6a10a8eb88022"
+checksum = "9ab5bcf04a2cdcbb50c7d6105de943f543f9ed92af55818fd17b660390fc8636"
 dependencies = [
  "libc",
  "pyo3-build-config",
@@ -1644,34 +1690,34 @@ dependencies = [
 
 [[package]]
 name = "pyo3-macros"
-version = "0.22.4"
+version = "0.22.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "15e0f01b5364bcfbb686a52fc4181d412b708a68ed20c330db9fc8d2c2bf5a43"
+checksum = "0fd24d897903a9e6d80b968368a34e1525aeb719d568dba8b3d4bfa5dc67d453"
 dependencies = [
  "proc-macro2",
  "pyo3-macros-backend",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "pyo3-macros-backend"
-version = "0.22.4"
+version = "0.22.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a09b550200e1e5ed9176976d0060cbc2ea82dc8515da07885e7b8153a85caacb"
+checksum = "36c011a03ba1e50152b4b394b479826cad97e7a21eb52df179cd91ac411cbfbe"
 dependencies = [
  "heck",
  "proc-macro2",
  "pyo3-build-config",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "quote"
-version = "1.0.37"
+version = "1.0.38"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b5b9d34b8991d19d98081b46eacdd8eb58c6f2b201139f7c5f643cc155a633af"
+checksum = "0e4dccaaaf89514f546c693ddc140f729f958c247918a13380cccc6078391acc"
 dependencies = [
  "proc-macro2",
 ]
@@ -1699,8 +1745,19 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "34af8d1a0e25924bc5b7c43c079c942339d8f0a8b57c39049bef581b46327404"
 dependencies = [
  "libc",
- "rand_chacha",
- "rand_core",
+ "rand_chacha 0.3.1",
+ "rand_core 0.6.4",
+]
+
+[[package]]
+name = "rand"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3779b94aeb87e8bd4e834cee3650289ee9e0d5677f976ecdb6d219e5f4f6cd94"
+dependencies = [
+ "rand_chacha 0.9.0",
+ "rand_core 0.9.1",
+ "zerocopy 0.8.18",
 ]
 
 [[package]]
@@ -1710,7 +1767,17 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.6.4",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3022b5f1df60f26e1ffddd6c66e8aa15de382ae63b3a0c1bfc0e4d3e3f325cb"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.9.1",
 ]
 
 [[package]]
@@ -1719,7 +1786,17 @@ version = "0.6.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ec0be4795e2f6a28069bec0b5ff3e2ac9bafc99e6a9a7dc3547996c5c816922c"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.15",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a88e0da7a2c97baa202165137c158d0a2e824ac465d13d81046727b34cb247d3"
+dependencies = [
+ "getrandom 0.3.1",
+ "zerocopy 0.8.18",
 ]
 
 [[package]]
@@ -1750,11 +1827,11 @@ checksum = "41cc0f7e4d5d4544e8861606a285bb08d3e70712ccc7d2b84d7c0ccfaf4b05ce"
 
 [[package]]
 name = "redox_syscall"
-version = "0.5.5"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62871f2d65009c0256aed1b9cfeeb8ac272833c404e13d53d400cd0dad7a2ac0"
+checksum = "03a862b389f93e68874fbf580b9de08dd02facb9a788ebadaf4a3fd33cf58834"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
 ]
 
 [[package]]
@@ -1763,9 +1840,9 @@ version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ba009ff324d1fc1b900bd1fdb31564febe58a8ccc8a6fdbb93b543d33b13ca43"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.15",
  "libredox",
- "thiserror",
+ "thiserror 1.0.69",
 ]
 
 [[package]]
@@ -1782,9 +1859,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.10.6"
+version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4219d74c6b67a3654a9fbebc4b419e22126d13d2f3c4a07ee0cb61ff79a79619"
+checksum = "b544ef1b4eac5dc2db33ea63606ae9ffcfac26c1416a2806ae0bf5f56b201191"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -1794,9 +1871,9 @@ dependencies = [
 
 [[package]]
 name = "regex-automata"
-version = "0.4.7"
+version = "0.4.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "38caf58cc5ef2fed281f89292ef23f6365465ed9a41b7a7754eb4e26496c92df"
+checksum = "809e8dc61f6de73b46c85f4c96486310fe304c434cfa43669d7b40f711150908"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -1805,9 +1882,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.8.4"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a66a03ae7c801facd77a29370b4faec201768915ac14a721ba36f20bc9c209b"
+checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 
 [[package]]
 name = "region"
@@ -1839,7 +1916,7 @@ dependencies = [
  "pmutil",
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -1859,15 +1936,15 @@ dependencies = [
 
 [[package]]
 name = "rustix"
-version = "0.38.37"
+version = "0.38.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8acb788b847c24f28525660c4d7758620a7210875711f79e7f663cc152726811"
+checksum = "fdb5bc1ae2baa591800df16c9ca78619bf65c0488b41b96ccec5d11220d8c154"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "errno",
  "libc",
  "linux-raw-sys",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -1895,8 +1972,7 @@ dependencies = [
 [[package]]
 name = "rustpython-ast"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4cdaf8ee5c1473b993b398c174641d3aa9da847af36e8d5eb8291930b72f31a5"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
  "is-macro",
  "malachite-bigint",
@@ -1910,14 +1986,15 @@ name = "rustpython-codegen"
 version = "0.4.0"
 dependencies = [
  "ahash",
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "indexmap",
  "insta",
- "itertools 0.11.0",
+ "itertools 0.14.0",
  "log",
  "num-complex",
  "num-traits",
  "rustpython-ast",
+ "rustpython-common",
  "rustpython-compiler-core",
  "rustpython-parser",
  "rustpython-parser-core",
@@ -1928,9 +2005,9 @@ name = "rustpython-common"
 version = "0.4.0"
 dependencies = [
  "ascii",
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
- "itertools 0.11.0",
+ "itertools 0.14.0",
  "libc",
  "lock_api",
  "malachite-base",
@@ -1941,9 +2018,9 @@ dependencies = [
  "once_cell",
  "parking_lot",
  "radium",
- "rand",
+ "rand 0.9.0",
  "rustpython-format",
- "siphasher",
+ "siphasher 0.3.11",
  "volatile",
  "widestring",
  "windows-sys 0.52.0",
@@ -1962,8 +2039,8 @@ dependencies = [
 name = "rustpython-compiler-core"
 version = "0.4.0"
 dependencies = [
- "bitflags 2.6.0",
- "itertools 0.11.0",
+ "bitflags 2.8.0",
+ "itertools 0.14.0",
  "lz4_flex",
  "malachite-bigint",
  "num-complex",
@@ -1977,14 +2054,14 @@ version = "0.4.0"
 dependencies = [
  "rustpython-compiler",
  "rustpython-derive-impl",
- "syn 1.0.109",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "rustpython-derive-impl"
 version = "0.4.0"
 dependencies = [
- "itertools 0.11.0",
+ "itertools 0.14.0",
  "maplit",
  "once_cell",
  "proc-macro2",
@@ -1992,9 +2069,9 @@ dependencies = [
  "rustpython-compiler-core",
  "rustpython-doc",
  "rustpython-parser-core",
- "syn 1.0.109",
+ "syn 2.0.98",
  "syn-ext",
- "textwrap 0.15.2",
+ "textwrap 0.16.1",
 ]
 
 [[package]]
@@ -2008,10 +2085,9 @@ dependencies = [
 [[package]]
 name = "rustpython-format"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0389039b132ad8e350552d771270ccd03186985696764bcee2239694e7839942"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "itertools 0.11.0",
  "malachite-bigint",
  "num-traits",
@@ -2030,14 +2106,13 @@ dependencies = [
  "num-traits",
  "rustpython-compiler-core",
  "rustpython-derive",
- "thiserror",
+ "thiserror 2.0.11",
 ]
 
 [[package]]
 name = "rustpython-literal"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a8304be3cae00232a1721a911033e55877ca3810215f66798e964a2d8d22281d"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
  "hexf-parse",
  "is-macro",
@@ -2049,8 +2124,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "868f724daac0caf9bd36d38caf45819905193a901e8f1c983345a68e18fb2abb"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
  "anyhow",
  "is-macro",
@@ -2073,8 +2147,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser-core"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b4b6c12fa273825edc7bccd9a734f0ad5ba4b8a2f4da5ff7efe946f066d0f4ad"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
  "is-macro",
  "memchr",
@@ -2084,8 +2157,7 @@ dependencies = [
 [[package]]
 name = "rustpython-parser-vendored"
 version = "0.4.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "04fcea49a4630a3a5d940f4d514dc4f575ed63c14c3e3ed07146634aed7f67a6"
+source = "git+https://github.com/RustPython/Parser.git?rev=d2f137b372ec08ce4a243564a80f8f9153c45a23#d2f137b372ec08ce4a243564a80f8f9153c45a23"
 dependencies = [
  "memchr",
  "once_cell",
@@ -2104,7 +2176,8 @@ dependencies = [
 name = "rustpython-sre_engine"
 version = "0.4.0"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
+ "criterion",
  "num_enum",
  "optional",
 ]
@@ -2131,18 +2204,18 @@ dependencies = [
  "gethostname",
  "hex",
  "indexmap",
- "itertools 0.11.0",
+ "itertools 0.14.0",
  "junction",
  "libc",
  "libsqlite3-sys",
- "libz-sys",
+ "libz-rs-sys",
  "mac_address",
  "malachite-bigint",
  "md-5",
  "memchr",
  "memmap2",
  "mt19937",
- "nix 0.29.0",
+ "nix",
  "num-complex",
  "num-integer",
  "num-traits",
@@ -2155,8 +2228,7 @@ dependencies = [
  "parking_lot",
  "paste",
  "puruspe",
- "rand",
- "rand_core",
+ "rand 0.9.0",
  "rustix",
  "rustpython-common",
  "rustpython-derive",
@@ -2191,29 +2263,31 @@ version = "0.4.0"
 dependencies = [
  "ahash",
  "ascii",
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "bstr",
  "caseless",
  "cfg-if",
  "chrono",
  "crossbeam-utils",
+ "errno",
  "exitcode",
  "flame",
  "flamer",
- "getrandom",
+ "getrandom 0.3.1",
  "glob",
  "half 2.4.1",
  "hex",
  "indexmap",
  "is-macro",
- "itertools 0.11.0",
+ "itertools 0.14.0",
  "junction",
  "libc",
+ "libloading",
  "log",
  "malachite-bigint",
  "memchr",
  "memoffset",
- "nix 0.29.0",
+ "nix",
  "num-complex",
  "num-integer",
  "num-traits",
@@ -2223,7 +2297,7 @@ dependencies = [
  "optional",
  "parking_lot",
  "paste",
- "rand",
+ "rand 0.9.0",
  "result-like",
  "rustc_version",
  "rustix",
@@ -2245,7 +2319,7 @@ dependencies = [
  "static_assertions",
  "strum",
  "strum_macros",
- "thiserror",
+ "thiserror 2.0.11",
  "thread_local",
  "timsort",
  "uname",
@@ -2267,6 +2341,7 @@ name = "rustpython_wasm"
 version = "0.4.0"
 dependencies = [
  "console_error_panic_hook",
+ "getrandom 0.2.15",
  "js-sys",
  "rustpython-common",
  "rustpython-parser",
@@ -2282,17 +2357,17 @@ dependencies = [
 
 [[package]]
 name = "rustversion"
-version = "1.0.17"
+version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "955d28af4278de8121b7ebeb796b6a45735dc01436d898801014aced2773a3d6"
+checksum = "f7c45b9784283f1b2e7fb61b42047c2fd678ef0960d4f6f1eba131594cc369d4"
 
 [[package]]
 name = "rustyline"
-version = "14.0.0"
+version = "15.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7803e8936da37efd9b6d4478277f4b2b9bb5cdb37a113e8d63222e58da647e63"
+checksum = "2ee1e066dc922e513bda599c6ccb5f3bb2b0ea5870a579448f2622993f0a9a2f"
 dependencies = [
- "bitflags 2.6.0",
+ "bitflags 2.8.0",
  "cfg-if",
  "clipboard-win",
  "fd-lock",
@@ -2300,19 +2375,19 @@ dependencies = [
  "libc",
  "log",
  "memchr",
- "nix 0.28.0",
+ "nix",
  "radix_trie",
  "unicode-segmentation",
- "unicode-width",
+ "unicode-width 0.2.0",
  "utf8parse",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
 name = "ryu"
-version = "1.0.18"
+version = "1.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3cb5ba0dc43242ce17de99c180e96db90b235b8a9fdc9543c96d2209116bd9f"
+checksum = "6ea1a2d0a644769cc99faa24c3ad26b379b786fe7c36fd3c546254801650e6dd"
 
 [[package]]
 name = "same-file"
@@ -2325,9 +2400,9 @@ dependencies = [
 
 [[package]]
 name = "schannel"
-version = "0.1.24"
+version = "0.1.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e9aaafd5a2b6e3d657ff009d82fbd630b6bd54dd4eb06f21693925cdf80f9b8b"
+checksum = "1f29ebaa345f945cec9fbbc532eb307f0fdad8161f281b6369539c8d84876b3d"
 dependencies = [
  "windows-sys 0.59.0",
 ]
@@ -2340,15 +2415,15 @@ checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
 
 [[package]]
 name = "semver"
-version = "1.0.23"
+version = "1.0.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61697e0a1c7e512e84a621326239844a24d8207b4669b41bc18b32ea5cbf988b"
+checksum = "f79dfe2d285b0488816f30e700a7438c5a73d816b5b7d3ac72fbc48b0d185e03"
 
 [[package]]
 name = "serde"
-version = "1.0.210"
+version = "1.0.217"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c8e3592472072e6e22e0a54d5904d9febf8508f65fb8552499a1abc7d1078c3a"
+checksum = "02fc4265df13d6fa1d00ecff087228cc0a2b5f3c0e87e258d8b94a156e984c70"
 dependencies = [
  "serde_derive",
 ]
@@ -2377,20 +2452,20 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.210"
+version = "1.0.217"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "243902eda00fad750862fc144cea25caca5e20d615af0a81bee94ca738f1df1f"
+checksum = "5a9bf7cf98d04a2b28aead066b7496853d4779c9cc183c440dbac457641e19a0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "serde_json"
-version = "1.0.128"
+version = "1.0.138"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ff5456707a1de34e7e37f2a6fd3d3f808c318259cbd01ab6377795054b483d8"
+checksum = "d434192e7da787e94a6ea7e9670b26a036d0ca41e0b7efb2676dd32bae872949"
 dependencies = [
  "itoa",
  "memchr",
@@ -2438,9 +2513,9 @@ checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
 [[package]]
 name = "similar"
-version = "2.6.0"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1de1d4f81173b03af4c0cbed3c898f6bff5b870e4a7f5d6f4057d62a7a4b686e"
+checksum = "bbbb5d9659141646ae647b42fe094daf6c6192d1620870b449d9557f748b2daa"
 
 [[package]]
 name = "siphasher"
@@ -2448,6 +2523,12 @@ version = "0.3.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "38b58827f4464d87d377d175e90bf58eb00fd8716ff0a62f80356b5e61555d0d"
 
+[[package]]
+name = "siphasher"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "56199f7ddabf13fe5074ce809e7d3f42b42ae711800501b5b16ea82ad029c39d"
+
 [[package]]
 name = "slice-group-by"
 version = "0.3.1"
@@ -2456,15 +2537,15 @@ checksum = "826167069c09b99d56f31e9ae5c99049e932a98c9dc2dac47645b08dbbf76ba7"
 
 [[package]]
 name = "smallvec"
-version = "1.13.2"
+version = "1.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3c5e1a9a646d36c3599cd173a41282daf47c44583ad367b8e6837255952e5c67"
+checksum = "7fcf8323ef1faaee30a44a340193b1ac6814fd9b7b4e88e9d4519a3e4abe1cfd"
 
 [[package]]
 name = "socket2"
-version = "0.5.7"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce305eb0b4296696835b71df73eb912e0f1ffd2556a501fcede6e0c50349191c"
+checksum = "c970269d99b64e60ec3bd6ad27270092a5394c4e309314b18ae3fe575695fbe8"
 dependencies = [
  "libc",
  "windows-sys 0.52.0",
@@ -2484,21 +2565,21 @@ checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
 [[package]]
 name = "strum"
-version = "0.26.3"
+version = "0.27.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8fec0f0aef304996cf250b31b5a10dee7980c85da9d759361292b8bca5a18f06"
+checksum = "f64def088c51c9510a8579e3c5d67c65349dcf755e5479ad3d010aa6454e2c32"
 
 [[package]]
 name = "strum_macros"
-version = "0.26.4"
+version = "0.27.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4c6bee85a5a24955dc440386795aa378cd9cf82acd5f764469152d2270e581be"
+checksum = "c77a8c5abcaf0f9ce05d62342b7d298c346515365c36b673df4ebe3ced01fde8"
 dependencies = [
  "heck",
  "proc-macro2",
  "quote",
  "rustversion",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -2520,9 +2601,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.77"
+version = "2.0.98"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9f35bcdf61fd8e7be6caf75f429fdca8beb3ed76584befb503b1569faee373ed"
+checksum = "36147f1a48ae0ec2b5b3bc5b537d267457555a10dc06f3dbc8cb11ba3006d3b1"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2531,11 +2612,13 @@ dependencies = [
 
 [[package]]
 name = "syn-ext"
-version = "0.4.0"
+version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9b86cb2b68c5b3c078cac02588bc23f3c04bb828c5d3aedd17980876ec6a7be6"
+checksum = "b126de4ef6c2a628a68609dd00733766c3b015894698a438ebdf374933fc31d1"
 dependencies = [
- "syn 1.0.109",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -2589,33 +2672,53 @@ version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
 dependencies = [
- "unicode-width",
+ "unicode-width 0.1.14",
 ]
 
 [[package]]
 name = "textwrap"
-version = "0.15.2"
+version = "0.16.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b7b3e525a49ec206798b40326a44121291b530c963cfb01018f63e135bac543d"
+checksum = "23d434d3f8967a09480fb04132ebe0a3e088c173e6d0ee7897abbdf4eab0f8b9"
 
 [[package]]
 name = "thiserror"
-version = "1.0.64"
+version = "1.0.69"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6aaf5339b578ea85b50e080feb250a3e8ae8cfcdff9a461c9ec2904bc923f52"
+dependencies = [
+ "thiserror-impl 1.0.69",
+]
+
+[[package]]
+name = "thiserror"
+version = "2.0.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d452f284b73e6d76dd36758a0c8684b1d5be31f92b89d07fd5822175732206fc"
+dependencies = [
+ "thiserror-impl 2.0.11",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d50af8abc119fb8bb6dbabcfa89656f46f84aa0ac7688088608076ad2b459a84"
+checksum = "4fee6c4efc90059e10f81e6d42c60a18f76588c3d74cb83a0b242a2b6c7504c1"
 dependencies = [
- "thiserror-impl",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.98",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.64"
+version = "2.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08904e7672f5eb876eaaf87e0ce17857500934f4981c4a0ab2b4aa98baac7fc3"
+checksum = "26afc1baea8a989337eeb52b6e72a039780ce45c3edfcc9c5b9d112feeb173c2"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
 
 [[package]]
@@ -2666,9 +2769,9 @@ dependencies = [
 
 [[package]]
 name = "tinyvec"
-version = "1.8.0"
+version = "1.8.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "445e881f4f6d382d5f27c034e25eb92edd7c784ceab92a0937db7f2e9471b938"
+checksum = "022db8904dfa342efe721985167e9fcd16c29b226db4397ed752a761cfce81e8"
 dependencies = [
  "tinyvec_macros",
 ]
@@ -2691,9 +2794,9 @@ dependencies = [
 
 [[package]]
 name = "typenum"
-version = "1.17.0"
+version = "1.18.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "42ff0bf0c66b8238c6f3b578df37d0b7848e55df8577b3f74f92a69acceeb825"
+checksum = "1dccffe3ce07af9386bfd29e80c0ab1a8205a2fc34e4bcd40364df902cfa8f3f"
 
 [[package]]
 name = "ucd"
@@ -2834,9 +2937,9 @@ checksum = "623f59e6af2a98bdafeb93fa277ac8e1e40440973001ca15cf4ae1541cd16d56"
 
 [[package]]
 name = "unicode-ident"
-version = "1.0.13"
+version = "1.0.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e91b56cd4cadaeb79bbf1a5645f6b4f8dc5bde8834ad5894a8db35fda9efa1fe"
+checksum = "a210d160f08b701c8721ba1c726c11662f877ea6b7094007e1ca9a1041945034"
 
 [[package]]
 name = "unicode-normalization"
@@ -2859,6 +2962,18 @@ version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7dd6e30e90baa6f72411720665d41d89b9a3d039dc45b8faea1ddd07f617f6af"
 
+[[package]]
+name = "unicode-width"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fc81956842c57dac11422a97c3b8195a1ff727f06e85c84ed2e8aa277c9a0fd"
+
+[[package]]
+name = "unicode-xid"
+version = "0.2.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"
+
 [[package]]
 name = "unicode_names2"
 version = "1.3.0"
@@ -2878,7 +2993,7 @@ dependencies = [
  "getopts",
  "log",
  "phf_codegen",
- "rand",
+ "rand 0.8.5",
 ]
 
 [[package]]
@@ -2895,13 +3010,11 @@ checksum = "06abde3611657adf66d383f00b093d7faecc7fa57071cce2578660c9f1010821"
 
 [[package]]
 name = "uuid"
-version = "1.10.0"
+version = "1.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "81dfa00651efa65069b0b6b651f4aaa31ba9e3c3ce0137aaad053604ee7e0314"
+checksum = "8c1f41ffb7cf259f1ecc2876861a17e7142e63ead296f671f81f6ae85903e0d6"
 dependencies = [
  "atomic",
- "getrandom",
- "rand",
 ]
 
 [[package]]
@@ -2944,48 +3057,59 @@ version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "wasi"
+version = "0.13.3+wasi-0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "26816d2e1a4a36a2940b96c5296ce403917633dff8f3440e9b236ed6f6bacad2"
+dependencies = [
+ "wit-bindgen-rt",
+]
+
 [[package]]
 name = "wasm-bindgen"
-version = "0.2.99"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a474f6281d1d70c17ae7aa6a613c87fce69a127e2624002df63dcb39d6cf6396"
+checksum = "1edc8929d7499fc4e8f0be2262a241556cfc54a0bea223790e71446f2aab1ef5"
 dependencies = [
  "cfg-if",
  "once_cell",
+ "rustversion",
  "wasm-bindgen-macro",
 ]
 
 [[package]]
 name = "wasm-bindgen-backend"
-version = "0.2.99"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5f89bb38646b4f81674e8f5c3fb81b562be1fd936d84320f3264486418519c79"
+checksum = "2f0a0651a5c2bc21487bde11ee802ccaf4c51935d0d3d42a6101f98161700bc6"
 dependencies = [
  "bumpalo",
  "log",
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
  "wasm-bindgen-shared",
 ]
 
 [[package]]
 name = "wasm-bindgen-futures"
-version = "0.4.43"
+version = "0.4.50"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61e9300f63a621e96ed275155c108eb6f843b6a26d053f122ab69724559dc8ed"
+checksum = "555d470ec0bc3bb57890405e5d4322cc9ea83cebb085523ced7be4144dac1e61"
 dependencies = [
  "cfg-if",
  "js-sys",
+ "once_cell",
  "wasm-bindgen",
  "web-sys",
 ]
 
 [[package]]
 name = "wasm-bindgen-macro"
-version = "0.2.99"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2cc6181fd9a7492eef6fef1f33961e3695e4579b9872a6f7c83aee556666d4fe"
+checksum = "7fe63fc6d09ed3792bd0897b314f53de8e16568c2b3f7982f468c0bf9bd0b407"
 dependencies = [
  "quote",
  "wasm-bindgen-macro-support",
@@ -2993,28 +3117,31 @@ dependencies = [
 
 [[package]]
 name = "wasm-bindgen-macro-support"
-version = "0.2.99"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "30d7a95b763d3c45903ed6c81f156801839e5ee968bb07e534c44df0fcd330c2"
+checksum = "8ae87ea40c9f689fc23f209965b6fb8a99ad69aeeb0231408be24920604395de"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
 
 [[package]]
 name = "wasm-bindgen-shared"
-version = "0.2.99"
+version = "0.2.100"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "943aab3fdaaa029a6e0271b35ea10b72b943135afe9bffca82384098ad0e06a6"
+checksum = "1a05d73b933a847d6cccdda8f838a22ff101ad9bf93e33684f39c1f5f0eece3d"
+dependencies = [
+ "unicode-ident",
+]
 
 [[package]]
 name = "web-sys"
-version = "0.3.70"
+version = "0.3.77"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "26fdeaafd9bd129f65e7c031593c24d62186301e0c72c8978fa1678be7d532c0"
+checksum = "33b6dd2ef9186f1f2072e409e99cd22a975331a6b3591b12c764e0e55c60d5d2"
 dependencies = [
  "js-sys",
  "wasm-bindgen",
@@ -3281,12 +3408,12 @@ checksum = "589f6da84c646204747d1270a2a5661ea66ed1cced2631d546fdfb155959f9ec"
 
 [[package]]
 name = "winreg"
-version = "0.52.0"
+version = "0.55.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a277a57398d4bfa075df44f501a17cfdf8542d224f0d36095a2adc7aee4ef0a5"
+checksum = "cb5a765337c50e9ec252c2069be9bf91c7df47afb103b642ba3a53bf8101be97"
 dependencies = [
  "cfg-if",
- "windows-sys 0.48.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -3295,11 +3422,20 @@ version = "0.0.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d135d17ab770252ad95e9a872d365cf3090e3be864a34ab46f48555993efc904"
 
+[[package]]
+name = "wit-bindgen-rt"
+version = "0.33.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3268f3d866458b787f390cf61f4bbb563b922d091359f9608842999eaee3943c"
+dependencies = [
+ "bitflags 2.8.0",
+]
+
 [[package]]
 name = "xml-rs"
-version = "0.8.22"
+version = "0.8.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "af4e2e2f7cba5a093896c1e150fbfe177d1883e7448200efb81d40b9d339ef26"
+checksum = "c5b940ebc25896e71dd073bad2dbaa2abfe97b0a391415e22ad1326d9c54e3c4"
 
 [[package]]
 name = "zerocopy"
@@ -3308,7 +3444,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b9b4fd18abc82b8136838da5d50bae7bdea537c574d8dc1a34ed098d6c166f0"
 dependencies = [
  "byteorder",
- "zerocopy-derive",
+ "zerocopy-derive 0.7.35",
+]
+
+[[package]]
+name = "zerocopy"
+version = "0.8.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "79386d31a42a4996e3336b0919ddb90f81112af416270cff95b5f5af22b839c2"
+dependencies = [
+ "zerocopy-derive 0.8.18",
 ]
 
 [[package]]
@@ -3319,5 +3464,22 @@ checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.77",
+ "syn 2.0.98",
 ]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.8.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "76331675d372f91bf8d17e13afbd5fe639200b73d01f0fc748bb059f9cca2db7"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.98",
+]
+
+[[package]]
+name = "zlib-rs"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b20717f0917c908dc63de2e44e97f1e6b126ca58d0e391cee86d504eb8fbd05"
diff --git a/Cargo.toml b/Cargo.toml
index af27add260..33fb96e84c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ repository.workspace = true
 license.workspace = true
 
 [features]
-default = ["threading", "stdlib", "zlib", "importlib"]
+default = ["threading", "stdlib", "importlib"]
 importlib = ["rustpython-vm/importlib"]
 encodings = ["rustpython-vm/encodings"]
 stdlib = ["rustpython-stdlib", "rustpython-pylib", "encodings"]
@@ -18,7 +18,6 @@ flame-it = ["rustpython-vm/flame-it", "flame", "flamescope"]
 freeze-stdlib = ["stdlib", "rustpython-vm/freeze-stdlib", "rustpython-pylib?/freeze-stdlib"]
 jit = ["rustpython-vm/jit"]
 threading = ["rustpython-vm/threading", "rustpython-stdlib/threading"]
-zlib = ["stdlib", "rustpython-stdlib/zlib"]
 bz2 = ["stdlib", "rustpython-stdlib/bz2"]
 sqlite = ["rustpython-stdlib/sqlite"]
 ssl = ["rustpython-stdlib/ssl"]
@@ -47,7 +46,7 @@ libc = { workspace = true }
 rustyline = { workspace = true }
 
 [dev-dependencies]
-criterion = { version = "0.3.5", features = ["html_reports"] }
+criterion = { workspace = true }
 pyo3 = { version = "0.22", features = ["auto-initialize"] }
 
 [[bench]]
@@ -103,8 +102,8 @@ members = [
 [workspace.package]
 version = "0.4.0"
 authors = ["RustPython Team"]
-edition = "2021"
-rust-version = "1.83.0"
+edition = "2024"
+rust-version = "1.85.0"
 repository = "https://github.com/RustPython/RustPython"
 license = "MIT"
 
@@ -122,16 +121,16 @@ rustpython-stdlib = { path = "stdlib", default-features = false, version = "0.4.
 rustpython-sre_engine = { path = "vm/sre_engine", version = "0.4.0" }
 rustpython-doc = { git = "https://github.com/RustPython/__doc__", tag = "0.3.0", version = "0.3.0" }
 
-rustpython-literal = { version = "0.4.0" }
-rustpython-parser-core = { version = "0.4.0" }
-rustpython-parser = { version = "0.4.0" }
-rustpython-ast = { version = "0.4.0" }
-rustpython-format= { version = "0.4.0" }
-# rustpython-literal = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "00d2f1d1a7522ef9c85c10dfa5f0bb7178dee655" }
-# rustpython-parser-core = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "00d2f1d1a7522ef9c85c10dfa5f0bb7178dee655" }
-# rustpython-parser = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "00d2f1d1a7522ef9c85c10dfa5f0bb7178dee655" }
-# rustpython-ast = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "00d2f1d1a7522ef9c85c10dfa5f0bb7178dee655" }
-# rustpython-format = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "00d2f1d1a7522ef9c85c10dfa5f0bb7178dee655" }
+# rustpython-literal = { version = "0.4.0" }
+# rustpython-parser-core = { version = "0.4.0" }
+# rustpython-parser = { version = "0.4.0" }
+# rustpython-ast = { version = "0.4.0" }
+# rustpython-format= { version = "0.4.0" }
+rustpython-literal = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "d2f137b372ec08ce4a243564a80f8f9153c45a23" }
+rustpython-parser-core = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "d2f137b372ec08ce4a243564a80f8f9153c45a23" }
+rustpython-parser = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "d2f137b372ec08ce4a243564a80f8f9153c45a23" }
+rustpython-ast = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "d2f137b372ec08ce4a243564a80f8f9153c45a23" }
+rustpython-format = { git = "https://github.com/RustPython/Parser.git", version = "0.4.0", rev = "d2f137b372ec08ce4a243564a80f8f9153c45a23" }
 # rustpython-literal = { path = "../RustPython-parser/literal" }
 # rustpython-parser-core = { path = "../RustPython-parser/core" }
 # rustpython-parser = { path = "../RustPython-parser/parser" }
@@ -139,55 +138,57 @@ rustpython-format= { version = "0.4.0" }
 # rustpython-format = { path = "../RustPython-parser/format" }
 
 ahash = "0.8.11"
-ascii = "1.0"
-bitflags = "2.4.1"
+ascii = "1.1"
+bitflags = "2.4.2"
 bstr = "1"
 cfg-if = "1.0"
-chrono = "0.4.37"
-crossbeam-utils = "0.8.19"
+chrono = "0.4.39"
+criterion = { version = "0.3.5", features = ["html_reports"] }
+crossbeam-utils = "0.8.21"
 flame = "0.2.2"
-getrandom = "0.2.12"
+getrandom = "0.3"
 glob = "0.3"
 hex = "0.4.3"
 indexmap = { version = "2.2.6", features = ["std"] }
 insta = "1.38.0"
-itertools = "0.11.0"
-is-macro = "0.3.0"
-junction = "1.0.0"
-libc = "0.2.153"
-log = "0.4.16"
+itertools = "0.14.0"
+is-macro = "0.3.7"
+junction = "1.2.0"
+libc = "0.2.169"
+log = "0.4.25"
 nix = { version = "0.29", features = ["fs", "user", "process", "term", "time", "signal", "ioctl", "socket", "sched", "zerocopy", "dir", "hostname", "net", "poll"] }
-malachite-bigint = "0.2.0"
-malachite-q = "0.4.4"
-malachite-base = "0.4.4"
-memchr = "2.7.2"
-num-complex = "0.4.0"
-num-integer = "0.1.44"
+malachite-bigint = "0.2.3"
+malachite-q = "0.4.22"
+malachite-base = "0.4.22"
+memchr = "2.7.4"
+num-complex = "0.4.6"
+num-integer = "0.1.46"
 num-traits = "0.2"
 num_enum = { version = "0.7", default-features = false }
-once_cell = "1.19.0"
-parking_lot = "0.12.1"
-paste = "1.0.7"
-rand = "0.8.5"
+once_cell = "1.20.3"
+parking_lot = "0.12.3"
+paste = "1.0.15"
+rand = "0.9"
 rustix = { version = "0.38", features = ["event"] }
-rustyline = "14.0.0"
+rustyline = "15.0.0"
 serde = { version = "1.0.133", default-features = false }
-schannel = "0.1.22"
+schannel = "0.1.27"
 static_assertions = "1.1"
-strum = "0.26"
-strum_macros = "0.26"
-syn = "1.0.109"
-thiserror = "1.0"
-thread_local = "1.1.4"
-unicode_names2 = "1.2.0"
+strum = "0.27"
+strum_macros = "0.27"
+syn = "2"
+thiserror = "2.0"
+thread_local = "1.1.8"
+unicode_names2 = "1.3.0"
 widestring = "1.1.0"
 windows-sys = "0.52.0"
-wasm-bindgen = "0.2.92"
+wasm-bindgen = "0.2.100"
 
 # Lints
 
 [workspace.lints.rust]
 unsafe_code = "allow"
+unsafe_op_in_unsafe_fn = "deny"
 
 [workspace.lints.clippy]
 perf = "warn"
diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index 7c79a011ba..aa7d99eef3 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -25,7 +25,7 @@ RustPython requires the following:
       stable version: `rustup update stable`
     - If you do not have Rust installed, use [rustup](https://rustup.rs/) to
       do so.
-- CPython version 3.12 or higher
+- CPython version 3.13 or higher
     - CPython can be installed by your operating system's package manager,
       from the [Python website](https://www.python.org/downloads/), or
       using a third-party distribution, such as 
diff --git a/LICENSE b/LICENSE
index 7213274e0f..e2aa2ed952 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020 RustPython Team
+Copyright (c) 2025 RustPython Team
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/Lib/_colorize.py b/Lib/_colorize.py
new file mode 100644
index 0000000000..70acfd4ad0
--- /dev/null
+++ b/Lib/_colorize.py
@@ -0,0 +1,67 @@
+import io
+import os
+import sys
+
+COLORIZE = True
+
+
+class ANSIColors:
+    BOLD_GREEN = "\x1b[1;32m"
+    BOLD_MAGENTA = "\x1b[1;35m"
+    BOLD_RED = "\x1b[1;31m"
+    GREEN = "\x1b[32m"
+    GREY = "\x1b[90m"
+    MAGENTA = "\x1b[35m"
+    RED = "\x1b[31m"
+    RESET = "\x1b[0m"
+    YELLOW = "\x1b[33m"
+
+
+NoColors = ANSIColors()
+
+for attr in dir(NoColors):
+    if not attr.startswith("__"):
+        setattr(NoColors, attr, "")
+
+
+def get_colors(colorize: bool = False, *, file=None) -> ANSIColors:
+    if colorize or can_colorize(file=file):
+        return ANSIColors()
+    else:
+        return NoColors
+
+
+def can_colorize(*, file=None) -> bool:
+    if file is None:
+        file = sys.stdout
+
+    if not sys.flags.ignore_environment:
+        if os.environ.get("PYTHON_COLORS") == "0":
+            return False
+        if os.environ.get("PYTHON_COLORS") == "1":
+            return True
+    if os.environ.get("NO_COLOR"):
+        return False
+    if not COLORIZE:
+        return False
+    if os.environ.get("FORCE_COLOR"):
+        return True
+    if os.environ.get("TERM") == "dumb":
+        return False
+
+    if not hasattr(file, "fileno"):
+        return False
+
+    if sys.platform == "win32":
+        try:
+            import nt
+
+            if not nt._supports_virtual_terminal():
+                return False
+        except (ImportError, AttributeError):
+            return False
+
+    try:
+        return os.isatty(file.fileno())
+    except io.UnsupportedOperation:
+        return file.isatty()
diff --git a/Lib/ctypes/test/test_numbers.py b/Lib/ctypes/test/test_numbers.py
index a7696376a5..a5c661b0e9 100644
--- a/Lib/ctypes/test/test_numbers.py
+++ b/Lib/ctypes/test/test_numbers.py
@@ -147,10 +147,10 @@ def test_alignments(self):
 
             # alignment of the type...
             self.assertEqual((code, alignment(t)),
-                                 (code, align))
+                             (code, align))
             # and alignment of an instance
             self.assertEqual((code, alignment(t())),
-                                 (code, align))
+                             (code, align))
 
     def test_int_from_address(self):
         from array import array
diff --git a/Lib/difflib.py b/Lib/difflib.py
index ba0b256969..3425e438c9 100644
--- a/Lib/difflib.py
+++ b/Lib/difflib.py
@@ -1200,25 +1200,6 @@ def context_diff(a, b, fromfile='', tofile='',
     strings for 'fromfile', 'tofile', 'fromfiledate', and 'tofiledate'.
     The modification times are normally expressed in the ISO 8601 format.
     If not specified, the strings default to blanks.
-
-    Example:
-
-    >>> print(''.join(context_diff('one\ntwo\nthree\nfour\n'.splitlines(True),
-    ...       'zero\none\ntree\nfour\n'.splitlines(True), 'Original', 'Current')),
-    ...       end="")
-    *** Original
-    --- Current
-    ***************
-    *** 1,4 ****
-      one
-    ! two
-    ! three
-      four
-    --- 1,4 ----
-    + zero
-      one
-    ! tree
-      four
     """
 
     _check_types(a, b, fromfile, tofile, fromfiledate, tofiledate, lineterm)
diff --git a/Lib/gzip.py b/Lib/gzip.py
index 5b20e5ba69..1a3c82ce7e 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -15,12 +15,16 @@
 
 FTEXT, FHCRC, FEXTRA, FNAME, FCOMMENT = 1, 2, 4, 8, 16
 
-READ, WRITE = 1, 2
+READ = 'rb'
+WRITE = 'wb'
 
 _COMPRESS_LEVEL_FAST = 1
 _COMPRESS_LEVEL_TRADEOFF = 6
 _COMPRESS_LEVEL_BEST = 9
 
+READ_BUFFER_SIZE = 128 * 1024
+_WRITE_BUFFER_SIZE = 4 * io.DEFAULT_BUFFER_SIZE
+
 
 def open(filename, mode="rb", compresslevel=_COMPRESS_LEVEL_BEST,
          encoding=None, errors=None, newline=None):
@@ -118,6 +122,21 @@ class BadGzipFile(OSError):
     """Exception raised in some cases for invalid gzip files."""
 
 
+class _WriteBufferStream(io.RawIOBase):
+    """Minimal object to pass WriteBuffer flushes into GzipFile"""
+    def __init__(self, gzip_file):
+        self.gzip_file = gzip_file
+
+    def write(self, data):
+        return self.gzip_file._write_raw(data)
+
+    def seekable(self):
+        return False
+
+    def writable(self):
+        return True
+
+
 class GzipFile(_compression.BaseStream):
     """The GzipFile class simulates most of the methods of a file object with
     the exception of the truncate() method.
@@ -160,9 +179,10 @@ def __init__(self, filename=None, mode=None,
         and 9 is slowest and produces the most compression. 0 is no compression
         at all. The default is 9.
 
-        The mtime argument is an optional numeric timestamp to be written
-        to the last modification time field in the stream when compressing.
-        If omitted or None, the current time is used.
+        The optional mtime argument is the timestamp requested by gzip. The time
+        is in Unix format, i.e., seconds since 00:00:00 UTC, January 1, 1970.
+        If mtime is omitted or None, the current time is used. Use mtime = 0
+        to generate a compressed stream that does not depend on creation time.
 
         """
 
@@ -182,6 +202,7 @@ def __init__(self, filename=None, mode=None,
         if mode is None:
             mode = getattr(fileobj, 'mode', 'rb')
 
+
         if mode.startswith('r'):
             self.mode = READ
             raw = _GzipReader(fileobj)
@@ -204,6 +225,9 @@ def __init__(self, filename=None, mode=None,
                                              zlib.DEF_MEM_LEVEL,
                                              0)
             self._write_mtime = mtime
+            self._buffer_size = _WRITE_BUFFER_SIZE
+            self._buffer = io.BufferedWriter(_WriteBufferStream(self),
+                                             buffer_size=self._buffer_size)
         else:
             raise ValueError("Invalid mode: {!r}".format(mode))
 
@@ -212,14 +236,6 @@ def __init__(self, filename=None, mode=None,
         if self.mode == WRITE:
             self._write_gzip_header(compresslevel)
 
-    @property
-    def filename(self):
-        import warnings
-        warnings.warn("use the name attribute", DeprecationWarning, 2)
-        if self.mode == WRITE and self.name[-3:] != ".gz":
-            return self.name + ".gz"
-        return self.name
-
     @property
     def mtime(self):
         """Last modification time read from stream, or None"""
@@ -237,6 +253,11 @@ def _init_write(self, filename):
         self.bufsize = 0
         self.offset = 0  # Current file offset for seek(), tell(), etc
 
+    def tell(self):
+        self._check_not_closed()
+        self._buffer.flush()
+        return super().tell()
+
     def _write_gzip_header(self, compresslevel):
         self.fileobj.write(b'\037\213')             # magic header
         self.fileobj.write(b'\010')                 # compression method
@@ -278,6 +299,10 @@ def write(self,data):
         if self.fileobj is None:
             raise ValueError("write() on closed GzipFile object")
 
+        return self._buffer.write(data)
+
+    def _write_raw(self, data):
+        # Called by our self._buffer underlying WriteBufferStream.
         if isinstance(data, (bytes, bytearray)):
             length = len(data)
         else:
@@ -326,11 +351,11 @@ def closed(self):
 
     def close(self):
         fileobj = self.fileobj
-        if fileobj is None:
+        if fileobj is None or self._buffer.closed:
             return
-        self.fileobj = None
         try:
             if self.mode == WRITE:
+                self._buffer.flush()
                 fileobj.write(self.compress.flush())
                 write32u(fileobj, self.crc)
                 # self.size may exceed 2 GiB, or even 4 GiB
@@ -338,6 +363,7 @@ def close(self):
             elif self.mode == READ:
                 self._buffer.close()
         finally:
+            self.fileobj = None
             myfileobj = self.myfileobj
             if myfileobj:
                 self.myfileobj = None
@@ -346,6 +372,7 @@ def close(self):
     def flush(self,zlib_mode=zlib.Z_SYNC_FLUSH):
         self._check_not_closed()
         if self.mode == WRITE:
+            self._buffer.flush()
             # Ensure the compressor's buffer is flushed
             self.fileobj.write(self.compress.flush(zlib_mode))
             self.fileobj.flush()
@@ -376,6 +403,9 @@ def seekable(self):
 
     def seek(self, offset, whence=io.SEEK_SET):
         if self.mode == WRITE:
+            self._check_not_closed()
+            # Flush buffer to ensure validity of self.offset
+            self._buffer.flush()
             if whence != io.SEEK_SET:
                 if whence == io.SEEK_CUR:
                     offset = self.offset + offset
@@ -384,10 +414,10 @@ def seek(self, offset, whence=io.SEEK_SET):
             if offset < self.offset:
                 raise OSError('Negative seek in write mode')
             count = offset - self.offset
-            chunk = b'\0' * 1024
-            for i in range(count // 1024):
+            chunk = b'\0' * self._buffer_size
+            for i in range(count // self._buffer_size):
                 self.write(chunk)
-            self.write(b'\0' * (count % 1024))
+            self.write(b'\0' * (count % self._buffer_size))
         elif self.mode == READ:
             self._check_not_closed()
             return self._buffer.seek(offset, whence)
@@ -454,7 +484,7 @@ def _read_gzip_header(fp):
 
 class _GzipReader(_compression.DecompressReader):
     def __init__(self, fp):
-        super().__init__(_PaddedFile(fp), zlib.decompressobj,
+        super().__init__(_PaddedFile(fp), zlib._ZlibDecompressor,
                          wbits=-zlib.MAX_WBITS)
         # Set flag indicating start of a new member
         self._new_member = True
@@ -502,12 +532,13 @@ def read(self, size=-1):
                 self._new_member = False
 
             # Read a chunk of data from the file
-            buf = self._fp.read(io.DEFAULT_BUFFER_SIZE)
+            if self._decompressor.needs_input:
+                buf = self._fp.read(READ_BUFFER_SIZE)
+                uncompress = self._decompressor.decompress(buf, size)
+            else:
+                uncompress = self._decompressor.decompress(b"", size)
 
-            uncompress = self._decompressor.decompress(buf, size)
-            if self._decompressor.unconsumed_tail != b"":
-                self._fp.prepend(self._decompressor.unconsumed_tail)
-            elif self._decompressor.unused_data != b"":
+            if self._decompressor.unused_data != b"":
                 # Prepend the already read bytes to the fileobj so they can
                 # be seen by _read_eof() and _read_gzip_header()
                 self._fp.prepend(self._decompressor.unused_data)
@@ -518,14 +549,11 @@ def read(self, size=-1):
                 raise EOFError("Compressed file ended before the "
                                "end-of-stream marker was reached")
 
-        self._add_read_data( uncompress )
+        self._crc = zlib.crc32(uncompress, self._crc)
+        self._stream_size += len(uncompress)
         self._pos += len(uncompress)
         return uncompress
 
-    def _add_read_data(self, data):
-        self._crc = zlib.crc32(data, self._crc)
-        self._stream_size = self._stream_size + len(data)
-
     def _read_eof(self):
         # We've read to the end of the file
         # We check that the computed CRC and size of the
@@ -552,43 +580,21 @@ def _rewind(self):
         self._new_member = True
 
 
-def _create_simple_gzip_header(compresslevel: int,
-                               mtime = None) -> bytes:
-    """
-    Write a simple gzip header with no extra fields.
-    :param compresslevel: Compresslevel used to determine the xfl bytes.
-    :param mtime: The mtime (must support conversion to a 32-bit integer).
-    :return: A bytes object representing the gzip header.
-    """
-    if mtime is None:
-        mtime = time.time()
-    if compresslevel == _COMPRESS_LEVEL_BEST:
-        xfl = 2
-    elif compresslevel == _COMPRESS_LEVEL_FAST:
-        xfl = 4
-    else:
-        xfl = 0
-    # Pack ID1 and ID2 magic bytes, method (8=deflate), header flags (no extra
-    # fields added to header), mtime, xfl and os (255 for unknown OS).
-    return struct.pack("<BBBBLBB", 0x1f, 0x8b, 8, 0, int(mtime), xfl, 255)
-
-
-def compress(data, compresslevel=_COMPRESS_LEVEL_BEST, *, mtime=None):
+def compress(data, compresslevel=_COMPRESS_LEVEL_BEST, *, mtime=0):
     """Compress data in one shot and return the compressed string.
 
     compresslevel sets the compression level in range of 0-9.
-    mtime can be used to set the modification time. The modification time is
-    set to the current time by default.
+    mtime can be used to set the modification time.
+    The modification time is set to 0 by default, for reproducibility.
     """
-    if mtime == 0:
-        # Use zlib as it creates the header with 0 mtime by default.
-        # This is faster and with less overhead.
-        return zlib.compress(data, level=compresslevel, wbits=31)
-    header = _create_simple_gzip_header(compresslevel, mtime)
-    trailer = struct.pack("<LL", zlib.crc32(data), (len(data) & 0xffffffff))
-    # Wbits=-15 creates a raw deflate block.
-    return (header + zlib.compress(data, level=compresslevel, wbits=-15) +
-            trailer)
+    # Wbits=31 automatically includes a gzip header and trailer.
+    gzip_data = zlib.compress(data, level=compresslevel, wbits=31)
+    if mtime is None:
+        mtime = time.time()
+    # Reuse gzip header created by zlib, replace mtime and OS byte for
+    # consistency.
+    header = struct.pack("<4sLBB", gzip_data, int(mtime), gzip_data[8], 255)
+    return header + gzip_data[10:]
 
 
 def decompress(data):
@@ -655,7 +661,7 @@ def main():
                 f = builtins.open(arg, "rb")
                 g = open(arg + ".gz", "wb")
         while True:
-            chunk = f.read(io.DEFAULT_BUFFER_SIZE)
+            chunk = f.read(READ_BUFFER_SIZE)
             if not chunk:
                 break
             g.write(chunk)
diff --git a/Lib/logging/__init__.py b/Lib/logging/__init__.py
index 19bd2bc20b..28df075dcd 100644
--- a/Lib/logging/__init__.py
+++ b/Lib/logging/__init__.py
@@ -1,4 +1,4 @@
-# Copyright 2001-2019 by Vinay Sajip. All Rights Reserved.
+# Copyright 2001-2022 by Vinay Sajip. All Rights Reserved.
 #
 # Permission to use, copy, modify, and distribute this software and its
 # documentation for any purpose and without fee is hereby granted,
@@ -18,13 +18,14 @@
 Logging package for Python. Based on PEP 282 and comments thereto in
 comp.lang.python.
 
-Copyright (C) 2001-2019 Vinay Sajip. All Rights Reserved.
+Copyright (C) 2001-2022 Vinay Sajip. All Rights Reserved.
 
 To use, simply 'import logging' and log away!
 """
 
 import sys, os, time, io, re, traceback, warnings, weakref, collections.abc
 
+from types import GenericAlias
 from string import Template
 from string import Formatter as StrFormatter
 
@@ -37,7 +38,8 @@
            'exception', 'fatal', 'getLevelName', 'getLogger', 'getLoggerClass',
            'info', 'log', 'makeLogRecord', 'setLoggerClass', 'shutdown',
            'warn', 'warning', 'getLogRecordFactory', 'setLogRecordFactory',
-           'lastResort', 'raiseExceptions']
+           'lastResort', 'raiseExceptions', 'getLevelNamesMapping',
+           'getHandlerByName', 'getHandlerNames']
 
 import threading
 
@@ -63,20 +65,25 @@
 raiseExceptions = True
 
 #
-# If you don't want threading information in the log, set this to zero
+# If you don't want threading information in the log, set this to False
 #
 logThreads = True
 
 #
-# If you don't want multiprocessing information in the log, set this to zero
+# If you don't want multiprocessing information in the log, set this to False
 #
 logMultiprocessing = True
 
 #
-# If you don't want process information in the log, set this to zero
+# If you don't want process information in the log, set this to False
 #
 logProcesses = True
 
+#
+# If you don't want asyncio task information in the log, set this to False
+#
+logAsyncioTasks = True
+
 #---------------------------------------------------------------------------
 #   Level related stuff
 #---------------------------------------------------------------------------
@@ -116,6 +123,9 @@
     'NOTSET': NOTSET,
 }
 
+def getLevelNamesMapping():
+    return _nameToLevel.copy()
+
 def getLevelName(level):
     """
     Return the textual or numeric representation of logging level 'level'.
@@ -156,15 +166,15 @@ def addLevelName(level, levelName):
     finally:
         _releaseLock()
 
-if hasattr(sys, '_getframe'):
-    currentframe = lambda: sys._getframe(3)
+if hasattr(sys, "_getframe"):
+    currentframe = lambda: sys._getframe(1)
 else: #pragma: no cover
     def currentframe():
         """Return the frame object for the caller's stack frame."""
         try:
             raise Exception
-        except Exception:
-            return sys.exc_info()[2].tb_frame.f_back
+        except Exception as exc:
+            return exc.__traceback__.tb_frame.f_back
 
 #
 # _srcfile is used when walking the stack to check when we've got the first
@@ -181,13 +191,18 @@ def currentframe():
 _srcfile = os.path.normcase(addLevelName.__code__.co_filename)
 
 # _srcfile is only used in conjunction with sys._getframe().
-# To provide compatibility with older versions of Python, set _srcfile
-# to None if _getframe() is not available; this value will prevent
-# findCaller() from being called. You can also do this if you want to avoid
-# the overhead of fetching caller information, even when _getframe() is
-# available.
-#if not hasattr(sys, '_getframe'):
-#    _srcfile = None
+# Setting _srcfile to None will prevent findCaller() from being called. This
+# way, you can avoid the overhead of fetching caller information.
+
+# The following is based on warnings._is_internal_frame. It makes sure that
+# frames of the import mechanism are skipped when logging at module level and
+# using a stacklevel value greater than one.
+def _is_internal_frame(frame):
+    """Signal whether the frame is a CPython or logging module internal."""
+    filename = os.path.normcase(frame.f_code.co_filename)
+    return filename == _srcfile or (
+            "importlib" in filename and "_bootstrap" in filename
+    )
 
 
 def _checkLevel(level):
@@ -307,7 +322,7 @@ def __init__(self, name, level, pathname, lineno,
         # Thus, while not removing the isinstance check, it does now look
         # for collections.abc.Mapping rather than, as before, dict.
         if (args and len(args) == 1 and isinstance(args[0], collections.abc.Mapping)
-            and args[0]):
+                and args[0]):
             args = args[0]
         self.args = args
         self.levelname = getLevelName(level)
@@ -325,7 +340,7 @@ def __init__(self, name, level, pathname, lineno,
         self.lineno = lineno
         self.funcName = func
         self.created = ct
-        self.msecs = (ct - int(ct)) * 1000
+        self.msecs = int((ct - int(ct)) * 1000) + 0.0  # see gh-89047
         self.relativeCreated = (self.created - _startTime) * 1000
         if logThreads:
             self.thread = threading.get_ident()
@@ -352,9 +367,18 @@ def __init__(self, name, level, pathname, lineno,
         else:
             self.process = None
 
+        self.taskName = None
+        if logAsyncioTasks:
+            asyncio = sys.modules.get('asyncio')
+            if asyncio:
+                try:
+                    self.taskName = asyncio.current_task().get_name()
+                except Exception:
+                    pass
+
     def __repr__(self):
         return '<LogRecord: %s, %s, %s, %s, "%s">'%(self.name, self.levelno,
-            self.pathname, self.lineno, self.msg)
+                                                    self.pathname, self.lineno, self.msg)
 
     def getMessage(self):
         """
@@ -487,7 +511,7 @@ def __init__(self, *args, **kwargs):
 
     def usesTime(self):
         fmt = self._fmt
-        return fmt.find('$asctime') >= 0 or fmt.find(self.asctime_format) >= 0
+        return fmt.find('$asctime') >= 0 or fmt.find(self.asctime_search) >= 0
 
     def validate(self):
         pattern = Template.pattern
@@ -557,6 +581,7 @@ class Formatter(object):
                         (typically at application startup time)
     %(thread)d          Thread ID (if available)
     %(threadName)s      Thread name (if available)
+    %(taskName)s        Task name (if available)
     %(process)d         Process ID (if available)
     %(message)s         The result of record.getMessage(), computed just as
                         the record is emitted
@@ -583,7 +608,7 @@ def __init__(self, fmt=None, datefmt=None, style='%', validate=True, *,
         """
         if style not in _STYLES:
             raise ValueError('Style must be one of: %s' % ','.join(
-                             _STYLES.keys()))
+                _STYLES.keys()))
         self._style = _STYLES[style][0](fmt, defaults=defaults)
         if validate:
             self._style.validate()
@@ -808,23 +833,36 @@ def filter(self, record):
         Determine if a record is loggable by consulting all the filters.
 
         The default is to allow the record to be logged; any filter can veto
-        this and the record is then dropped. Returns a zero value if a record
-        is to be dropped, else non-zero.
+        this by returning a false value.
+        If a filter attached to a handler returns a log record instance,
+        then that instance is used in place of the original log record in
+        any further processing of the event by that handler.
+        If a filter returns any other true value, the original log record
+        is used in any further processing of the event by that handler.
+
+        If none of the filters return false values, this method returns
+        a log record.
+        If any of the filters return a false value, this method returns
+        a false value.
 
         .. versionchanged:: 3.2
 
            Allow filters to be just callables.
+
+        .. versionchanged:: 3.12
+           Allow filters to return a LogRecord instead of
+           modifying it in place.
         """
-        rv = True
         for f in self.filters:
             if hasattr(f, 'filter'):
                 result = f.filter(record)
             else:
                 result = f(record) # assume callable - will raise if not
             if not result:
-                rv = False
-                break
-        return rv
+                return False
+            if isinstance(result, LogRecord):
+                record = result
+        return record
 
 #---------------------------------------------------------------------------
 #   Handler classes and functions
@@ -845,8 +883,9 @@ def _removeHandlerRef(wr):
     if acquire and release and handlers:
         acquire()
         try:
-            if wr in handlers:
-                handlers.remove(wr)
+            handlers.remove(wr)
+        except ValueError:
+            pass
         finally:
             release()
 
@@ -860,6 +899,23 @@ def _addHandlerRef(handler):
     finally:
         _releaseLock()
 
+
+def getHandlerByName(name):
+    """
+    Get a handler with the specified *name*, or None if there isn't one with
+    that name.
+    """
+    return _handlers.get(name)
+
+
+def getHandlerNames():
+    """
+    Return all known handler names as an immutable set.
+    """
+    result = set(_handlers.keys())
+    return frozenset(result)
+
+
 class Handler(Filterer):
     """
     Handler instances dispatch logging events to specific destinations.
@@ -958,10 +1014,14 @@ def handle(self, record):
 
         Emission depends on filters which may have been added to the handler.
         Wrap the actual emission of the record with acquisition/release of
-        the I/O thread lock. Returns whether the filter passed the record for
-        emission.
+        the I/O thread lock.
+
+        Returns an instance of the log record that was emitted
+        if it passed all filters, otherwise a false value is returned.
         """
         rv = self.filter(record)
+        if isinstance(rv, LogRecord):
+            record = rv
         if rv:
             self.acquire()
             try:
@@ -1032,7 +1092,7 @@ def handleError(self, record):
                 else:
                     # couldn't find the right stack frame, for some reason
                     sys.stderr.write('Logged from file %s, line %s\n' % (
-                                     record.filename, record.lineno))
+                        record.filename, record.lineno))
                 # Issue 18671: output logging message and arguments
                 try:
                     sys.stderr.write('Message: %r\n'
@@ -1044,7 +1104,7 @@ def handleError(self, record):
                     sys.stderr.write('Unable to print the message and arguments'
                                      ' - possible formatting error.\nUse the'
                                      ' traceback above to help find the error.\n'
-                                    )
+                                     )
             except OSError: #pragma: no cover
                 pass    # see issue 5971
             finally:
@@ -1136,6 +1196,8 @@ def __repr__(self):
             name += ' '
         return '<%s %s(%s)>' % (self.__class__.__name__, name, level)
 
+    __class_getitem__ = classmethod(GenericAlias)
+
 
 class FileHandler(StreamHandler):
     """
@@ -1459,7 +1521,7 @@ def debug(self, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.debug("Houston, we have a %s", "thorny problem", exc_info=1)
+        logger.debug("Houston, we have a %s", "thorny problem", exc_info=True)
         """
         if self.isEnabledFor(DEBUG):
             self._log(DEBUG, msg, args, **kwargs)
@@ -1471,7 +1533,7 @@ def info(self, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.info("Houston, we have a %s", "interesting problem", exc_info=1)
+        logger.info("Houston, we have a %s", "notable problem", exc_info=True)
         """
         if self.isEnabledFor(INFO):
             self._log(INFO, msg, args, **kwargs)
@@ -1483,14 +1545,14 @@ def warning(self, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.warning("Houston, we have a %s", "bit of a problem", exc_info=1)
+        logger.warning("Houston, we have a %s", "bit of a problem", exc_info=True)
         """
         if self.isEnabledFor(WARNING):
             self._log(WARNING, msg, args, **kwargs)
 
     def warn(self, msg, *args, **kwargs):
         warnings.warn("The 'warn' method is deprecated, "
-            "use 'warning' instead", DeprecationWarning, 2)
+                      "use 'warning' instead", DeprecationWarning, 2)
         self.warning(msg, *args, **kwargs)
 
     def error(self, msg, *args, **kwargs):
@@ -1500,7 +1562,7 @@ def error(self, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.error("Houston, we have a %s", "major problem", exc_info=1)
+        logger.error("Houston, we have a %s", "major problem", exc_info=True)
         """
         if self.isEnabledFor(ERROR):
             self._log(ERROR, msg, args, **kwargs)
@@ -1518,7 +1580,7 @@ def critical(self, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.critical("Houston, we have a %s", "major disaster", exc_info=1)
+        logger.critical("Houston, we have a %s", "major disaster", exc_info=True)
         """
         if self.isEnabledFor(CRITICAL):
             self._log(CRITICAL, msg, args, **kwargs)
@@ -1536,7 +1598,7 @@ def log(self, level, msg, *args, **kwargs):
         To pass exception information, use the keyword argument exc_info with
         a true value, e.g.
 
-        logger.log(level, "We have a %s", "mysterious problem", exc_info=1)
+        logger.log(level, "We have a %s", "mysterious problem", exc_info=True)
         """
         if not isinstance(level, int):
             if raiseExceptions:
@@ -1554,33 +1616,31 @@ def findCaller(self, stack_info=False, stacklevel=1):
         f = currentframe()
         #On some versions of IronPython, currentframe() returns None if
         #IronPython isn't run with -X:Frames.
-        if f is not None:
-            f = f.f_back
-        orig_f = f
-        while f and stacklevel > 1:
-            f = f.f_back
-            stacklevel -= 1
-        if not f:
-            f = orig_f
-        rv = "(unknown file)", 0, "(unknown function)", None
-        while hasattr(f, "f_code"):
-            co = f.f_code
-            filename = os.path.normcase(co.co_filename)
-            if filename == _srcfile:
-                f = f.f_back
-                continue
-            sinfo = None
-            if stack_info:
-                sio = io.StringIO()
-                sio.write('Stack (most recent call last):\n')
+        if f is None:
+            return "(unknown file)", 0, "(unknown function)", None
+        while stacklevel > 0:
+            next_f = f.f_back
+            if next_f is None:
+                ## We've got options here.
+                ## If we want to use the last (deepest) frame:
+                break
+                ## If we want to mimic the warnings module:
+                #return ("sys", 1, "(unknown function)", None)
+                ## If we want to be pedantic:
+                #raise ValueError("call stack is not deep enough")
+            f = next_f
+            if not _is_internal_frame(f):
+                stacklevel -= 1
+        co = f.f_code
+        sinfo = None
+        if stack_info:
+            with io.StringIO() as sio:
+                sio.write("Stack (most recent call last):\n")
                 traceback.print_stack(f, file=sio)
                 sinfo = sio.getvalue()
                 if sinfo[-1] == '\n':
                     sinfo = sinfo[:-1]
-                sio.close()
-            rv = (co.co_filename, f.f_lineno, co.co_name, sinfo)
-            break
-        return rv
+        return co.co_filename, f.f_lineno, co.co_name, sinfo
 
     def makeRecord(self, name, level, fn, lno, msg, args, exc_info,
                    func=None, extra=None, sinfo=None):
@@ -1589,7 +1649,7 @@ def makeRecord(self, name, level, fn, lno, msg, args, exc_info,
         specialized LogRecords.
         """
         rv = _logRecordFactory(name, level, fn, lno, msg, args, exc_info, func,
-                             sinfo)
+                               sinfo)
         if extra is not None:
             for key in extra:
                 if (key in ["message", "asctime"]) or (key in rv.__dict__):
@@ -1630,8 +1690,14 @@ def handle(self, record):
         This method is used for unpickled records received from a socket, as
         well as those created locally. Logger-level filtering is applied.
         """
-        if (not self.disabled) and self.filter(record):
-            self.callHandlers(record)
+        if self.disabled:
+            return
+        maybe_record = self.filter(record)
+        if not maybe_record:
+            return
+        if isinstance(maybe_record, LogRecord):
+            record = maybe_record
+        self.callHandlers(record)
 
     def addHandler(self, hdlr):
         """
@@ -1737,7 +1803,7 @@ def isEnabledFor(self, level):
                     is_enabled = self._cache[level] = False
                 else:
                     is_enabled = self._cache[level] = (
-                        level >= self.getEffectiveLevel()
+                            level >= self.getEffectiveLevel()
                     )
             finally:
                 _releaseLock()
@@ -1762,13 +1828,30 @@ def getChild(self, suffix):
             suffix = '.'.join((self.name, suffix))
         return self.manager.getLogger(suffix)
 
+    def getChildren(self):
+
+        def _hierlevel(logger):
+            if logger is logger.manager.root:
+                return 0
+            return 1 + logger.name.count('.')
+
+        d = self.manager.loggerDict
+        _acquireLock()
+        try:
+            # exclude PlaceHolders - the last check is to ensure that lower-level
+            # descendants aren't returned - if there are placeholders, a logger's
+            # parent field might point to a grandparent or ancestor thereof.
+            return set(item for item in d.values()
+                       if isinstance(item, Logger) and item.parent is self and
+                       _hierlevel(item) == 1 + _hierlevel(item.parent))
+        finally:
+            _releaseLock()
+
     def __repr__(self):
         level = getLevelName(self.getEffectiveLevel())
         return '<%s %s (%s)>' % (self.__class__.__name__, self.name, level)
 
     def __reduce__(self):
-        # In general, only the root logger will not be accessible via its name.
-        # However, the root logger's class has its own __reduce__ method.
         if getLogger(self.name) is not self:
             import pickle
             raise pickle.PicklingError('logger cannot be pickled')
@@ -1848,7 +1931,7 @@ def warning(self, msg, *args, **kwargs):
 
     def warn(self, msg, *args, **kwargs):
         warnings.warn("The 'warn' method is deprecated, "
-            "use 'warning' instead", DeprecationWarning, 2)
+                      "use 'warning' instead", DeprecationWarning, 2)
         self.warning(msg, *args, **kwargs)
 
     def error(self, msg, *args, **kwargs):
@@ -1902,18 +1985,11 @@ def hasHandlers(self):
         """
         return self.logger.hasHandlers()
 
-    def _log(self, level, msg, args, exc_info=None, extra=None, stack_info=False):
+    def _log(self, level, msg, args, **kwargs):
         """
         Low-level log implementation, proxied to allow nested logger adapters.
         """
-        return self.logger._log(
-            level,
-            msg,
-            args,
-            exc_info=exc_info,
-            extra=extra,
-            stack_info=stack_info,
-        )
+        return self.logger._log(level, msg, args, **kwargs)
 
     @property
     def manager(self):
@@ -1932,6 +2008,8 @@ def __repr__(self):
         level = getLevelName(logger.getEffectiveLevel())
         return '<%s %s (%s)>' % (self.__class__.__name__, logger.name, level)
 
+    __class_getitem__ = classmethod(GenericAlias)
+
 root = RootLogger(WARNING)
 Logger.root = root
 Logger.manager = Manager(Logger.root)
@@ -1971,7 +2049,7 @@ def basicConfig(**kwargs):
               that this argument is incompatible with 'filename' - if both
               are present, 'stream' is ignored.
     handlers  If specified, this should be an iterable of already created
-              handlers, which will be added to the root handler. Any handler
+              handlers, which will be added to the root logger. Any handler
               in the list which does not have a formatter assigned will be
               assigned the formatter created in this function.
     force     If this keyword  is specified as true, any existing handlers
@@ -2047,7 +2125,7 @@ def basicConfig(**kwargs):
             style = kwargs.pop("style", '%')
             if style not in _STYLES:
                 raise ValueError('Style must be one of: %s' % ','.join(
-                                 _STYLES.keys()))
+                    _STYLES.keys()))
             fs = kwargs.pop("format", _STYLES[style][1])
             fmt = Formatter(fs, dfs, style)
             for h in handlers:
@@ -2124,7 +2202,7 @@ def warning(msg, *args, **kwargs):
 
 def warn(msg, *args, **kwargs):
     warnings.warn("The 'warn' function is deprecated, "
-        "use 'warning' instead", DeprecationWarning, 2)
+                  "use 'warning' instead", DeprecationWarning, 2)
     warning(msg, *args, **kwargs)
 
 def info(msg, *args, **kwargs):
@@ -2179,7 +2257,11 @@ def shutdown(handlerList=_handlerList):
             if h:
                 try:
                     h.acquire()
-                    h.flush()
+                    # MemoryHandlers might not want to be flushed on close,
+                    # but circular imports prevent us scoping this to just
+                    # those handlers.  hence the default to True.
+                    if getattr(h, 'flushOnClose', True):
+                        h.flush()
                     h.close()
                 except (OSError, ValueError):
                     # Ignore errors which might be caused
@@ -2242,7 +2324,9 @@ def _showwarning(message, category, filename, lineno, file=None, line=None):
         logger = getLogger("py.warnings")
         if not logger.handlers:
             logger.addHandler(NullHandler())
-        logger.warning("%s", s)
+        # bpo-46557: Log str(s) as msg instead of logger.warning("%s", s)
+        # since some log aggregation tools group logs by the msg arg
+        logger.warning(str(s))
 
 def captureWarnings(capture):
     """
diff --git a/Lib/logging/config.py b/Lib/logging/config.py
index 3bc63b7862..ef04a35168 100644
--- a/Lib/logging/config.py
+++ b/Lib/logging/config.py
@@ -1,4 +1,4 @@
-# Copyright 2001-2019 by Vinay Sajip. All Rights Reserved.
+# Copyright 2001-2023 by Vinay Sajip. All Rights Reserved.
 #
 # Permission to use, copy, modify, and distribute this software and its
 # documentation for any purpose and without fee is hereby granted,
@@ -19,18 +19,20 @@
 is based on PEP 282 and comments thereto in comp.lang.python, and influenced
 by Apache's log4j system.
 
-Copyright (C) 2001-2019 Vinay Sajip. All Rights Reserved.
+Copyright (C) 2001-2022 Vinay Sajip. All Rights Reserved.
 
 To use, simply 'import logging' and log away!
 """
 
 import errno
+import functools
 import io
 import logging
 import logging.handlers
+import os
+import queue
 import re
 import struct
-import sys
 import threading
 import traceback
 
@@ -59,15 +61,24 @@ def fileConfig(fname, defaults=None, disable_existing_loggers=True, encoding=Non
     """
     import configparser
 
+    if isinstance(fname, str):
+        if not os.path.exists(fname):
+            raise FileNotFoundError(f"{fname} doesn't exist")
+        elif not os.path.getsize(fname):
+            raise RuntimeError(f'{fname} is an empty file')
+
     if isinstance(fname, configparser.RawConfigParser):
         cp = fname
     else:
-        cp = configparser.ConfigParser(defaults)
-        if hasattr(fname, 'readline'):
-            cp.read_file(fname)
-        else:
-            encoding = io.text_encoding(encoding)
-            cp.read(fname, encoding=encoding)
+        try:
+            cp = configparser.ConfigParser(defaults)
+            if hasattr(fname, 'readline'):
+                cp.read_file(fname)
+            else:
+                encoding = io.text_encoding(encoding)
+                cp.read(fname, encoding=encoding)
+        except configparser.ParsingError as e:
+            raise RuntimeError(f'{fname} is invalid: {e}')
 
     formatters = _create_formatters(cp)
 
@@ -113,11 +124,18 @@ def _create_formatters(cp):
         fs = cp.get(sectname, "format", raw=True, fallback=None)
         dfs = cp.get(sectname, "datefmt", raw=True, fallback=None)
         stl = cp.get(sectname, "style", raw=True, fallback='%')
+        defaults = cp.get(sectname, "defaults", raw=True, fallback=None)
+
         c = logging.Formatter
         class_name = cp[sectname].get("class")
         if class_name:
             c = _resolve(class_name)
-        f = c(fs, dfs, stl)
+
+        if defaults is not None:
+            defaults = eval(defaults, vars(logging))
+            f = c(fs, dfs, stl, defaults=defaults)
+        else:
+            f = c(fs, dfs, stl)
         formatters[form] = f
     return formatters
 
@@ -296,7 +314,7 @@ def convert_with_key(self, key, value, replace=True):
             if replace:
                 self[key] = result
             if type(result) in (ConvertingDict, ConvertingList,
-                               ConvertingTuple):
+                                ConvertingTuple):
                 result.parent = self
                 result.key = key
         return result
@@ -305,7 +323,7 @@ def convert(self, value):
         result = self.configurator.convert(value)
         if value is not result:
             if type(result) in (ConvertingDict, ConvertingList,
-                               ConvertingTuple):
+                                ConvertingTuple):
                 result.parent = self
         return result
 
@@ -392,11 +410,9 @@ def resolve(self, s):
                     self.importer(used)
                     found = getattr(found, frag)
             return found
-        except ImportError:
-            e, tb = sys.exc_info()[1:]
+        except ImportError as e:
             v = ValueError('Cannot resolve %r: %s' % (s, e))
-            v.__cause__, v.__traceback__ = e, tb
-            raise v
+            raise v from e
 
     def ext_convert(self, value):
         """Default converter for the ext:// protocol."""
@@ -448,8 +464,8 @@ def convert(self, value):
         elif not isinstance(value, ConvertingList) and isinstance(value, list):
             value = ConvertingList(value)
             value.configurator = self
-        elif not isinstance(value, ConvertingTuple) and\
-                 isinstance(value, tuple) and not hasattr(value, '_fields'):
+        elif not isinstance(value, ConvertingTuple) and \
+                isinstance(value, tuple) and not hasattr(value, '_fields'):
             value = ConvertingTuple(value)
             value.configurator = self
         elif isinstance(value, str): # str for py3k
@@ -469,10 +485,10 @@ def configure_custom(self, config):
         c = config.pop('()')
         if not callable(c):
             c = self.resolve(c)
-        props = config.pop('.', None)
         # Check for valid identifiers
-        kwargs = {k: config[k] for k in config if valid_ident(k)}
+        kwargs = {k: config[k] for k in config if (k != '.' and valid_ident(k))}
         result = c(**kwargs)
+        props = config.pop('.', None)
         if props:
             for name, value in props.items():
                 setattr(result, name, value)
@@ -484,6 +500,33 @@ def as_tuple(self, value):
             value = tuple(value)
         return value
 
+def _is_queue_like_object(obj):
+    """Check that *obj* implements the Queue API."""
+    if isinstance(obj, (queue.Queue, queue.SimpleQueue)):
+        return True
+    # defer importing multiprocessing as much as possible
+    from multiprocessing.queues import Queue as MPQueue
+    if isinstance(obj, MPQueue):
+        return True
+    # Depending on the multiprocessing start context, we cannot create
+    # a multiprocessing.managers.BaseManager instance 'mm' to get the
+    # runtime type of mm.Queue() or mm.JoinableQueue() (see gh-119819).
+    #
+    # Since we only need an object implementing the Queue API, we only
+    # do a protocol check, but we do not use typing.runtime_checkable()
+    # and typing.Protocol to reduce import time (see gh-121723).
+    #
+    # Ideally, we would have wanted to simply use strict type checking
+    # instead of a protocol-based type checking since the latter does
+    # not check the method signatures.
+    #
+    # Note that only 'put_nowait' and 'get' are required by the logging
+    # queue handler and queue listener (see gh-124653) and that other
+    # methods are either optional or unused.
+    minimal_queue_interface = ['put_nowait', 'get']
+    return all(callable(getattr(obj, method, None))
+               for method in minimal_queue_interface)
+
 class DictConfigurator(BaseConfigurator):
     """
     Configure logging using a dictionary-like object to describe the
@@ -542,7 +585,7 @@ def configure(self):
                 for name in formatters:
                     try:
                         formatters[name] = self.configure_formatter(
-                                                            formatters[name])
+                            formatters[name])
                     except Exception as e:
                         raise ValueError('Unable to configure '
                                          'formatter %r' % name) from e
@@ -566,7 +609,7 @@ def configure(self):
                         handler.name = name
                         handlers[name] = handler
                     except Exception as e:
-                        if 'target not configured yet' in str(e.__cause__):
+                        if ' not configured yet' in str(e.__cause__):
                             deferred.append(name)
                         else:
                             raise ValueError('Unable to configure handler '
@@ -669,18 +712,27 @@ def configure_formatter(self, config):
             dfmt = config.get('datefmt', None)
             style = config.get('style', '%')
             cname = config.get('class', None)
+            defaults = config.get('defaults', None)
 
             if not cname:
                 c = logging.Formatter
             else:
                 c = _resolve(cname)
 
+            kwargs  = {}
+
+            # Add defaults only if it exists.
+            # Prevents TypeError in custom formatter callables that do not
+            # accept it.
+            if defaults is not None:
+                kwargs['defaults'] = defaults
+
             # A TypeError would be raised if "validate" key is passed in with a formatter callable
             # that does not accept "validate" as a parameter
             if 'validate' in config:  # if user hasn't mentioned it, the default will be fine
-                result = c(fmt, dfmt, style, config['validate'])
+                result = c(fmt, dfmt, style, config['validate'], **kwargs)
             else:
-                result = c(fmt, dfmt, style)
+                result = c(fmt, dfmt, style, **kwargs)
 
         return result
 
@@ -697,10 +749,29 @@ def add_filters(self, filterer, filters):
         """Add filters to a filterer from a list of names."""
         for f in filters:
             try:
-                filterer.addFilter(self.config['filters'][f])
+                if callable(f) or callable(getattr(f, 'filter', None)):
+                    filter_ = f
+                else:
+                    filter_ = self.config['filters'][f]
+                filterer.addFilter(filter_)
             except Exception as e:
                 raise ValueError('Unable to add filter %r' % f) from e
 
+    def _configure_queue_handler(self, klass, **kwargs):
+        if 'queue' in kwargs:
+            q = kwargs.pop('queue')
+        else:
+            q = queue.Queue()  # unbounded
+
+        rhl = kwargs.pop('respect_handler_level', False)
+        lklass = kwargs.pop('listener', logging.handlers.QueueListener)
+        handlers = kwargs.pop('handlers', [])
+
+        listener = lklass(q, *handlers, respect_handler_level=rhl)
+        handler = klass(q, **kwargs)
+        handler.listener = listener
+        return handler
+
     def configure_handler(self, config):
         """Configure a handler from a dictionary."""
         config_copy = dict(config)  # for restoring in case of error
@@ -720,28 +791,87 @@ def configure_handler(self, config):
             factory = c
         else:
             cname = config.pop('class')
-            klass = self.resolve(cname)
-            #Special case for handler which refers to another handler
-            if issubclass(klass, logging.handlers.MemoryHandler) and\
-                'target' in config:
-                try:
-                    th = self.config['handlers'][config['target']]
-                    if not isinstance(th, logging.Handler):
-                        config.update(config_copy)  # restore for deferred cfg
-                        raise TypeError('target not configured yet')
-                    config['target'] = th
-                except Exception as e:
-                    raise ValueError('Unable to set target handler '
-                                     '%r' % config['target']) from e
-            elif issubclass(klass, logging.handlers.SMTPHandler) and\
-                'mailhost' in config:
+            if callable(cname):
+                klass = cname
+            else:
+                klass = self.resolve(cname)
+            if issubclass(klass, logging.handlers.MemoryHandler):
+                if 'flushLevel' in config:
+                    config['flushLevel'] = logging._checkLevel(config['flushLevel'])
+                if 'target' in config:
+                    # Special case for handler which refers to another handler
+                    try:
+                        tn = config['target']
+                        th = self.config['handlers'][tn]
+                        if not isinstance(th, logging.Handler):
+                            config.update(config_copy)  # restore for deferred cfg
+                            raise TypeError('target not configured yet')
+                        config['target'] = th
+                    except Exception as e:
+                        raise ValueError('Unable to set target handler %r' % tn) from e
+            elif issubclass(klass, logging.handlers.QueueHandler):
+                # Another special case for handler which refers to other handlers
+                # if 'handlers' not in config:
+                # raise ValueError('No handlers specified for a QueueHandler')
+                if 'queue' in config:
+                    qspec = config['queue']
+
+                    if isinstance(qspec, str):
+                        q = self.resolve(qspec)
+                        if not callable(q):
+                            raise TypeError('Invalid queue specifier %r' % qspec)
+                        config['queue'] = q()
+                    elif isinstance(qspec, dict):
+                        if '()' not in qspec:
+                            raise TypeError('Invalid queue specifier %r' % qspec)
+                        config['queue'] = self.configure_custom(dict(qspec))
+                    elif not _is_queue_like_object(qspec):
+                        raise TypeError('Invalid queue specifier %r' % qspec)
+
+                if 'listener' in config:
+                    lspec = config['listener']
+                    if isinstance(lspec, type):
+                        if not issubclass(lspec, logging.handlers.QueueListener):
+                            raise TypeError('Invalid listener specifier %r' % lspec)
+                    else:
+                        if isinstance(lspec, str):
+                            listener = self.resolve(lspec)
+                            if isinstance(listener, type) and \
+                                    not issubclass(listener, logging.handlers.QueueListener):
+                                raise TypeError('Invalid listener specifier %r' % lspec)
+                        elif isinstance(lspec, dict):
+                            if '()' not in lspec:
+                                raise TypeError('Invalid listener specifier %r' % lspec)
+                            listener = self.configure_custom(dict(lspec))
+                        else:
+                            raise TypeError('Invalid listener specifier %r' % lspec)
+                        if not callable(listener):
+                            raise TypeError('Invalid listener specifier %r' % lspec)
+                        config['listener'] = listener
+                if 'handlers' in config:
+                    hlist = []
+                    try:
+                        for hn in config['handlers']:
+                            h = self.config['handlers'][hn]
+                            if not isinstance(h, logging.Handler):
+                                config.update(config_copy)  # restore for deferred cfg
+                                raise TypeError('Required handler %r '
+                                                'is not configured yet' % hn)
+                            hlist.append(h)
+                    except Exception as e:
+                        raise ValueError('Unable to set required handler %r' % hn) from e
+                    config['handlers'] = hlist
+            elif issubclass(klass, logging.handlers.SMTPHandler) and \
+                    'mailhost' in config:
                 config['mailhost'] = self.as_tuple(config['mailhost'])
-            elif issubclass(klass, logging.handlers.SysLogHandler) and\
-                'address' in config:
+            elif issubclass(klass, logging.handlers.SysLogHandler) and \
+                    'address' in config:
                 config['address'] = self.as_tuple(config['address'])
-            factory = klass
-        props = config.pop('.', None)
-        kwargs = {k: config[k] for k in config if valid_ident(k)}
+            if issubclass(klass, logging.handlers.QueueHandler):
+                factory = functools.partial(self._configure_queue_handler, klass)
+            else:
+                factory = klass
+        kwargs = {k: config[k] for k in config if (k != '.' and valid_ident(k))}
         try:
             result = factory(**kwargs)
         except TypeError as te:
@@ -759,6 +889,7 @@ def configure_handler(self, config):
             result.setLevel(logging._checkLevel(level))
         if filters:
             self.add_filters(result, filters)
+        props = config.pop('.', None)
         if props:
             for name, value in props.items():
                 setattr(result, name, value)
@@ -794,6 +925,7 @@ def configure_logger(self, name, config, incremental=False):
         """Configure a non-root logger from a dictionary."""
         logger = logging.getLogger(name)
         self.common_logger_config(logger, config, incremental)
+        logger.disabled = False
         propagate = config.get('propagate', None)
         if propagate is not None:
             logger.propagate = propagate
diff --git a/Lib/logging/handlers.py b/Lib/logging/handlers.py
index 61a39958c0..bf42ea1103 100644
--- a/Lib/logging/handlers.py
+++ b/Lib/logging/handlers.py
@@ -187,15 +187,18 @@ def shouldRollover(self, record):
         Basically, see if the supplied record would cause the file to exceed
         the size limit we have.
         """
-        # See bpo-45401: Never rollover anything other than regular files
-        if os.path.exists(self.baseFilename) and not os.path.isfile(self.baseFilename):
-            return False
         if self.stream is None:                 # delay was set...
             self.stream = self._open()
         if self.maxBytes > 0:                   # are we rolling over?
+            pos = self.stream.tell()
+            if not pos:
+                # gh-116263: Never rollover an empty file
+                return False
             msg = "%s\n" % self.format(record)
-            self.stream.seek(0, 2)  #due to non-posix-compliant Windows feature
-            if self.stream.tell() + len(msg) >= self.maxBytes:
+            if pos + len(msg) >= self.maxBytes:
+                # See bpo-45401: Never rollover anything other than regular files
+                if os.path.exists(self.baseFilename) and not os.path.isfile(self.baseFilename):
+                    return False
                 return True
         return False
 
@@ -232,19 +235,19 @@ def __init__(self, filename, when='h', interval=1, backupCount=0,
         if self.when == 'S':
             self.interval = 1 # one second
             self.suffix = "%Y-%m-%d_%H-%M-%S"
-            self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}(\.\w+)?$"
+            extMatch = r"(?<!\d)\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}(?!\d)"
         elif self.when == 'M':
             self.interval = 60 # one minute
             self.suffix = "%Y-%m-%d_%H-%M"
-            self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}(\.\w+)?$"
+            extMatch = r"(?<!\d)\d{4}-\d{2}-\d{2}_\d{2}-\d{2}(?!\d)"
         elif self.when == 'H':
             self.interval = 60 * 60 # one hour
             self.suffix = "%Y-%m-%d_%H"
-            self.extMatch = r"^\d{4}-\d{2}-\d{2}_\d{2}(\.\w+)?$"
+            extMatch = r"(?<!\d)\d{4}-\d{2}-\d{2}_\d{2}(?!\d)"
         elif self.when == 'D' or self.when == 'MIDNIGHT':
             self.interval = 60 * 60 * 24 # one day
             self.suffix = "%Y-%m-%d"
-            self.extMatch = r"^\d{4}-\d{2}-\d{2}(\.\w+)?$"
+            extMatch = r"(?<!\d)\d{4}-\d{2}-\d{2}(?!\d)"
         elif self.when.startswith('W'):
             self.interval = 60 * 60 * 24 * 7 # one week
             if len(self.when) != 2:
@@ -253,11 +256,17 @@ def __init__(self, filename, when='h', interval=1, backupCount=0,
                 raise ValueError("Invalid day specified for weekly rollover: %s" % self.when)
             self.dayOfWeek = int(self.when[1])
             self.suffix = "%Y-%m-%d"
-            self.extMatch = r"^\d{4}-\d{2}-\d{2}(\.\w+)?$"
+            extMatch = r"(?<!\d)\d{4}-\d{2}-\d{2}(?!\d)"
         else:
             raise ValueError("Invalid rollover interval specified: %s" % self.when)
 
-        self.extMatch = re.compile(self.extMatch, re.ASCII)
+        # extMatch is a pattern for matching a datetime suffix in a file name.
+        # After custom naming, it is no longer guaranteed to be separated by
+        # periods from other parts of the filename.  The lookup statements
+        # (?<!\d) and (?!\d) ensure that the datetime suffix (which itself
+        # starts and ends with digits) is not preceded or followed by digits.
+        # This reduces the number of false matches and improves performance.
+        self.extMatch = re.compile(extMatch, re.ASCII)
         self.interval = self.interval * interval # multiply by units requested
         # The following line added because the filename passed in could be a
         # path object (see Issue #27493), but self.baseFilename will be a string
@@ -295,11 +304,11 @@ def computeRollover(self, currentTime):
                 rotate_ts = _MIDNIGHT
             else:
                 rotate_ts = ((self.atTime.hour * 60 + self.atTime.minute)*60 +
-                    self.atTime.second)
+                             self.atTime.second)
 
             r = rotate_ts - ((currentHour * 60 + currentMinute) * 60 +
-                currentSecond)
-            if r < 0:
+                             currentSecond)
+            if r <= 0:
                 # Rotate time is before the current time (for example when
                 # self.rotateAt is 13:45 and it now 14:15), rotation is
                 # tomorrow.
@@ -328,17 +337,21 @@ def computeRollover(self, currentTime):
                         daysToWait = self.dayOfWeek - day
                     else:
                         daysToWait = 6 - day + self.dayOfWeek + 1
-                    newRolloverAt = result + (daysToWait * (60 * 60 * 24))
-                    if not self.utc:
-                        dstNow = t[-1]
-                        dstAtRollover = time.localtime(newRolloverAt)[-1]
-                        if dstNow != dstAtRollover:
-                            if not dstNow:  # DST kicks in before next rollover, so we need to deduct an hour
-                                addend = -3600
-                            else:           # DST bows out before next rollover, so we need to add an hour
-                                addend = 3600
-                            newRolloverAt += addend
-                    result = newRolloverAt
+                    result += daysToWait * _MIDNIGHT
+                result += self.interval - _MIDNIGHT * 7
+            else:
+                result += self.interval - _MIDNIGHT
+            if not self.utc:
+                dstNow = t[-1]
+                dstAtRollover = time.localtime(result)[-1]
+                if dstNow != dstAtRollover:
+                    if not dstNow:  # DST kicks in before next rollover, so we need to deduct an hour
+                        addend = -3600
+                        if not time.localtime(result-3600)[-1]:
+                            addend = 0
+                    else:           # DST bows out before next rollover, so we need to add an hour
+                        addend = 3600
+                    result += addend
         return result
 
     def shouldRollover(self, record):
@@ -348,11 +361,15 @@ def shouldRollover(self, record):
         record is not used, as we are just comparing times, but it is needed so
         the method signatures are the same
         """
-        # See bpo-45401: Never rollover anything other than regular files
-        if os.path.exists(self.baseFilename) and not os.path.isfile(self.baseFilename):
-            return False
         t = int(time.time())
         if t >= self.rolloverAt:
+            # See #89564: Never rollover anything other than regular files
+            if os.path.exists(self.baseFilename) and not os.path.isfile(self.baseFilename):
+                # The file is not a regular file, so do not rollover, but do
+                # set the next rollover time to avoid repeated checks.
+                self.rolloverAt = self.computeRollover(t)
+                return False
+
             return True
         return False
 
@@ -365,32 +382,28 @@ def getFilesToDelete(self):
         dirName, baseName = os.path.split(self.baseFilename)
         fileNames = os.listdir(dirName)
         result = []
-        # See bpo-44753: Don't use the extension when computing the prefix.
-        n, e = os.path.splitext(baseName)
-        prefix = n + '.'
-        plen = len(prefix)
-        for fileName in fileNames:
-            if self.namer is None:
-                # Our files will always start with baseName
-                if not fileName.startswith(baseName):
-                    continue
-            else:
-                # Our files could be just about anything after custom naming, but
-                # likely candidates are of the form
-                # foo.log.DATETIME_SUFFIX or foo.DATETIME_SUFFIX.log
-                if (not fileName.startswith(baseName) and fileName.endswith(e) and
-                    len(fileName) > (plen + 1) and not fileName[plen+1].isdigit()):
-                    continue
-
-            if fileName[:plen] == prefix:
-                suffix = fileName[plen:]
-                # See bpo-45628: The date/time suffix could be anywhere in the
-                # filename
-                parts = suffix.split('.')
-                for part in parts:
-                    if self.extMatch.match(part):
+        if self.namer is None:
+            prefix = baseName + '.'
+            plen = len(prefix)
+            for fileName in fileNames:
+                if fileName[:plen] == prefix:
+                    suffix = fileName[plen:]
+                    if self.extMatch.fullmatch(suffix):
+                        result.append(os.path.join(dirName, fileName))
+        else:
+            for fileName in fileNames:
+                # Our files could be just about anything after custom naming,
+                # but they should contain the datetime suffix.
+                # Try to find the datetime suffix in the file name and verify
+                # that the file name can be generated by this handler.
+                m = self.extMatch.search(fileName)
+                while m:
+                    dfn = self.namer(self.baseFilename + "." + m[0])
+                    if os.path.basename(dfn) == fileName:
                         result.append(os.path.join(dirName, fileName))
                         break
+                    m = self.extMatch.search(fileName, m.start() + 1)
+
         if len(result) < self.backupCount:
             result = []
         else:
@@ -406,17 +419,14 @@ def doRollover(self):
         then we have to get a list of matching filenames, sort them and remove
         the one with the oldest suffix.
         """
-        if self.stream:
-            self.stream.close()
-            self.stream = None
         # get the time that this sequence started at and make it a TimeTuple
         currentTime = int(time.time())
-        dstNow = time.localtime(currentTime)[-1]
         t = self.rolloverAt - self.interval
         if self.utc:
             timeTuple = time.gmtime(t)
         else:
             timeTuple = time.localtime(t)
+            dstNow = time.localtime(currentTime)[-1]
             dstThen = timeTuple[-1]
             if dstNow != dstThen:
                 if dstNow:
@@ -427,26 +437,19 @@ def doRollover(self):
         dfn = self.rotation_filename(self.baseFilename + "." +
                                      time.strftime(self.suffix, timeTuple))
         if os.path.exists(dfn):
-            os.remove(dfn)
+            # Already rolled over.
+            return
+
+        if self.stream:
+            self.stream.close()
+            self.stream = None
         self.rotate(self.baseFilename, dfn)
         if self.backupCount > 0:
             for s in self.getFilesToDelete():
                 os.remove(s)
         if not self.delay:
             self.stream = self._open()
-        newRolloverAt = self.computeRollover(currentTime)
-        while newRolloverAt <= currentTime:
-            newRolloverAt = newRolloverAt + self.interval
-        #If DST changes and midnight or weekly rollover, adjust for this.
-        if (self.when == 'MIDNIGHT' or self.when.startswith('W')) and not self.utc:
-            dstAtRollover = time.localtime(newRolloverAt)[-1]
-            if dstNow != dstAtRollover:
-                if not dstNow:  # DST kicks in before next rollover, so we need to deduct an hour
-                    addend = -3600
-                else:           # DST bows out before next rollover, so we need to add an hour
-                    addend = 3600
-                newRolloverAt += addend
-        self.rolloverAt = newRolloverAt
+        self.rolloverAt = self.computeRollover(currentTime)
 
 class WatchedFileHandler(logging.FileHandler):
     """
@@ -800,7 +803,7 @@ class SysLogHandler(logging.Handler):
         "panic":    LOG_EMERG,      #  DEPRECATED
         "warn":     LOG_WARNING,    #  DEPRECATED
         "warning":  LOG_WARNING,
-        }
+    }
 
     facility_names = {
         "auth":         LOG_AUTH,
@@ -827,12 +830,10 @@ class SysLogHandler(logging.Handler):
         "local5":       LOG_LOCAL5,
         "local6":       LOG_LOCAL6,
         "local7":       LOG_LOCAL7,
-        }
+    }
 
-    #The map below appears to be trivially lowercasing the key. However,
-    #there's more to it than meets the eye - in some locales, lowercasing
-    #gives unexpected results. See SF #1524081: in the Turkish locale,
-    #"INFO".lower() != "info"
+    # Originally added to work around GH-43683. Unnecessary since GH-50043 but kept
+    # for backwards compatibility.
     priority_map = {
         "DEBUG" : "debug",
         "INFO" : "info",
@@ -859,12 +860,49 @@ def __init__(self, address=('localhost', SYSLOG_UDP_PORT),
         self.address = address
         self.facility = facility
         self.socktype = socktype
+        self.socket = None
+        self.createSocket()
+
+    def _connect_unixsocket(self, address):
+        use_socktype = self.socktype
+        if use_socktype is None:
+            use_socktype = socket.SOCK_DGRAM
+        self.socket = socket.socket(socket.AF_UNIX, use_socktype)
+        try:
+            self.socket.connect(address)
+            # it worked, so set self.socktype to the used type
+            self.socktype = use_socktype
+        except OSError:
+            self.socket.close()
+            if self.socktype is not None:
+                # user didn't specify falling back, so fail
+                raise
+            use_socktype = socket.SOCK_STREAM
+            self.socket = socket.socket(socket.AF_UNIX, use_socktype)
+            try:
+                self.socket.connect(address)
+                # it worked, so set self.socktype to the used type
+                self.socktype = use_socktype
+            except OSError:
+                self.socket.close()
+                raise
+
+    def createSocket(self):
+        """
+        Try to create a socket and, if it's not a datagram socket, connect it
+        to the other end. This method is called during handler initialization,
+        but it's not regarded as an error if the other end isn't listening yet
+        --- the method will be called again when emitting an event,
+        if there is no socket at that point.
+        """
+        address = self.address
+        socktype = self.socktype
 
         if isinstance(address, str):
             self.unixsocket = True
             # Syslog server may be unavailable during handler initialisation.
             # C's openlog() function also ignores connection errors.
-            # Moreover, we ignore these errors while logging, so it not worse
+            # Moreover, we ignore these errors while logging, so it's not worse
             # to ignore it also here.
             try:
                 self._connect_unixsocket(address)
@@ -895,30 +933,6 @@ def __init__(self, address=('localhost', SYSLOG_UDP_PORT),
             self.socket = sock
             self.socktype = socktype
 
-    def _connect_unixsocket(self, address):
-        use_socktype = self.socktype
-        if use_socktype is None:
-            use_socktype = socket.SOCK_DGRAM
-        self.socket = socket.socket(socket.AF_UNIX, use_socktype)
-        try:
-            self.socket.connect(address)
-            # it worked, so set self.socktype to the used type
-            self.socktype = use_socktype
-        except OSError:
-            self.socket.close()
-            if self.socktype is not None:
-                # user didn't specify falling back, so fail
-                raise
-            use_socktype = socket.SOCK_STREAM
-            self.socket = socket.socket(socket.AF_UNIX, use_socktype)
-            try:
-                self.socket.connect(address)
-                # it worked, so set self.socktype to the used type
-                self.socktype = use_socktype
-            except OSError:
-                self.socket.close()
-                raise
-
     def encodePriority(self, facility, priority):
         """
         Encode the facility and priority. You can pass in strings or
@@ -938,7 +952,10 @@ def close(self):
         """
         self.acquire()
         try:
-            self.socket.close()
+            sock = self.socket
+            if sock:
+                self.socket = None
+                sock.close()
             logging.Handler.close(self)
         finally:
             self.release()
@@ -978,6 +995,10 @@ def emit(self, record):
             # Message is a string. Convert to bytes as required by RFC 5424
             msg = msg.encode('utf-8')
             msg = prio + msg
+
+            if not self.socket:
+                self.createSocket()
+
             if self.unixsocket:
                 try:
                     self.socket.send(msg)
@@ -1094,7 +1115,16 @@ def __init__(self, appname, dllname=None, logtype="Application"):
                 dllname = os.path.join(dllname[0], r'win32service.pyd')
             self.dllname = dllname
             self.logtype = logtype
-            self._welu.AddSourceToRegistry(appname, dllname, logtype)
+            # Administrative privileges are required to add a source to the registry.
+            # This may not be available for a user that just wants to add to an
+            # existing source - handle this specific case.
+            try:
+                self._welu.AddSourceToRegistry(appname, dllname, logtype)
+            except Exception as e:
+                # This will probably be a pywintypes.error. Only raise if it's not
+                # an "access denied" error, else let it pass
+                if getattr(e, 'winerror', None) != 5:  # not access denied
+                    raise
             self.deftype = win32evtlog.EVENTLOG_ERROR_TYPE
             self.typemap = {
                 logging.DEBUG   : win32evtlog.EVENTLOG_INFORMATION_TYPE,
@@ -1102,10 +1132,10 @@ def __init__(self, appname, dllname=None, logtype="Application"):
                 logging.WARNING : win32evtlog.EVENTLOG_WARNING_TYPE,
                 logging.ERROR   : win32evtlog.EVENTLOG_ERROR_TYPE,
                 logging.CRITICAL: win32evtlog.EVENTLOG_ERROR_TYPE,
-         }
+            }
         except ImportError:
-            print("The Python Win32 extensions for NT (service, event "\
-                        "logging) appear not to be available.")
+            print("The Python Win32 extensions for NT (service, event " \
+                  "logging) appear not to be available.")
             self._welu = None
 
     def getMessageID(self, record):
@@ -1348,7 +1378,7 @@ def shouldFlush(self, record):
         Check for buffer full or a record at the flushLevel or higher.
         """
         return (len(self.buffer) >= self.capacity) or \
-                (record.levelno >= self.flushLevel)
+            (record.levelno >= self.flushLevel)
 
     def setTarget(self, target):
         """
@@ -1366,7 +1396,7 @@ def flush(self):
         records to the target, if there is one. Override if you want
         different behaviour.
 
-        The record buffer is also cleared by this operation.
+        The record buffer is only cleared if a target has been set.
         """
         self.acquire()
         try:
@@ -1411,6 +1441,7 @@ def __init__(self, queue):
         """
         logging.Handler.__init__(self)
         self.queue = queue
+        self.listener = None  # will be set to listener if configured via dictConfig()
 
     def enqueue(self, record):
         """
@@ -1424,12 +1455,15 @@ def enqueue(self, record):
 
     def prepare(self, record):
         """
-        Prepares a record for queuing. The object returned by this method is
+        Prepare a record for queuing. The object returned by this method is
         enqueued.
 
-        The base implementation formats the record to merge the message
-        and arguments, and removes unpickleable items from the record
-        in-place.
+        The base implementation formats the record to merge the message and
+        arguments, and removes unpickleable items from the record in-place.
+        Specifically, it overwrites the record's `msg` and
+        `message` attributes with the merged message (obtained by
+        calling the handler's `format` method), and sets the `args`,
+        `exc_info` and `exc_text` attributes to None.
 
         You might want to override this method if you want to convert
         the record to a dict or JSON string, or send a modified copy
@@ -1439,7 +1473,7 @@ def prepare(self, record):
         # (if there's exception data), and also returns the formatted
         # message. We can then use this to replace the original
         # msg + args, as these might be unpickleable. We also zap the
-        # exc_info and exc_text attributes, as they are no longer
+        # exc_info, exc_text and stack_info attributes, as they are no longer
         # needed and, if not None, will typically not be pickleable.
         msg = self.format(record)
         # bpo-35726: make copy of record to avoid affecting other handlers in the chain.
@@ -1449,6 +1483,7 @@ def prepare(self, record):
         record.args = None
         record.exc_info = None
         record.exc_text = None
+        record.stack_info = None
         return record
 
     def emit(self, record):
diff --git a/Lib/smtplib.py b/Lib/smtplib.py
new file mode 100644
index 0000000000..912233d817
--- /dev/null
+++ b/Lib/smtplib.py
@@ -0,0 +1,1109 @@
+#! /usr/bin/env python3
+
+'''SMTP/ESMTP client class.
+
+This should follow RFC 821 (SMTP), RFC 1869 (ESMTP), RFC 2554 (SMTP
+Authentication) and RFC 2487 (Secure SMTP over TLS).
+
+Notes:
+
+Please remember, when doing ESMTP, that the names of the SMTP service
+extensions are NOT the same thing as the option keywords for the RCPT
+and MAIL commands!
+
+Example:
+
+  >>> import smtplib
+  >>> s=smtplib.SMTP("localhost")
+  >>> print(s.help())
+  This is Sendmail version 8.8.4
+  Topics:
+      HELO    EHLO    MAIL    RCPT    DATA
+      RSET    NOOP    QUIT    HELP    VRFY
+      EXPN    VERB    ETRN    DSN
+  For more info use "HELP <topic>".
+  To report bugs in the implementation send email to
+      sendmail-bugs@sendmail.org.
+  For local information send email to Postmaster at your site.
+  End of HELP info
+  >>> s.putcmd("vrfy","someone@here")
+  >>> s.getreply()
+  (250, "Somebody OverHere <somebody@here.my.org>")
+  >>> s.quit()
+'''
+
+# Author: The Dragon De Monsyne <dragondm@integral.org>
+# ESMTP support, test code and doc fixes added by
+#     Eric S. Raymond <esr@thyrsus.com>
+# Better RFC 821 compliance (MAIL and RCPT, and CRLF in data)
+#     by Carey Evans <c.evans@clear.net.nz>, for picky mail servers.
+# RFC 2554 (authentication) support by Gerhard Haering <gerhard@bigfoot.de>.
+#
+# This was modified from the Python 1.5 library HTTP lib.
+
+import socket
+import io
+import re
+import email.utils
+import email.message
+import email.generator
+import base64
+import hmac
+import copy
+import datetime
+import sys
+from email.base64mime import body_encode as encode_base64
+
+__all__ = ["SMTPException", "SMTPNotSupportedError", "SMTPServerDisconnected", "SMTPResponseException",
+           "SMTPSenderRefused", "SMTPRecipientsRefused", "SMTPDataError",
+           "SMTPConnectError", "SMTPHeloError", "SMTPAuthenticationError",
+           "quoteaddr", "quotedata", "SMTP"]
+
+SMTP_PORT = 25
+SMTP_SSL_PORT = 465
+CRLF = "\r\n"
+bCRLF = b"\r\n"
+_MAXLINE = 8192 # more than 8 times larger than RFC 821, 4.5.3
+_MAXCHALLENGE = 5  # Maximum number of AUTH challenges sent
+
+OLDSTYLE_AUTH = re.compile(r"auth=(.*)", re.I)
+
+# Exception classes used by this module.
+class SMTPException(OSError):
+    """Base class for all exceptions raised by this module."""
+
+class SMTPNotSupportedError(SMTPException):
+    """The command or option is not supported by the SMTP server.
+
+    This exception is raised when an attempt is made to run a command or a
+    command with an option which is not supported by the server.
+    """
+
+class SMTPServerDisconnected(SMTPException):
+    """Not connected to any SMTP server.
+
+    This exception is raised when the server unexpectedly disconnects,
+    or when an attempt is made to use the SMTP instance before
+    connecting it to a server.
+    """
+
+class SMTPResponseException(SMTPException):
+    """Base class for all exceptions that include an SMTP error code.
+
+    These exceptions are generated in some instances when the SMTP
+    server returns an error code.  The error code is stored in the
+    `smtp_code' attribute of the error, and the `smtp_error' attribute
+    is set to the error message.
+    """
+
+    def __init__(self, code, msg):
+        self.smtp_code = code
+        self.smtp_error = msg
+        self.args = (code, msg)
+
+class SMTPSenderRefused(SMTPResponseException):
+    """Sender address refused.
+
+    In addition to the attributes set by on all SMTPResponseException
+    exceptions, this sets `sender' to the string that the SMTP refused.
+    """
+
+    def __init__(self, code, msg, sender):
+        self.smtp_code = code
+        self.smtp_error = msg
+        self.sender = sender
+        self.args = (code, msg, sender)
+
+class SMTPRecipientsRefused(SMTPException):
+    """All recipient addresses refused.
+
+    The errors for each recipient are accessible through the attribute
+    'recipients', which is a dictionary of exactly the same sort as
+    SMTP.sendmail() returns.
+    """
+
+    def __init__(self, recipients):
+        self.recipients = recipients
+        self.args = (recipients,)
+
+
+class SMTPDataError(SMTPResponseException):
+    """The SMTP server didn't accept the data."""
+
+class SMTPConnectError(SMTPResponseException):
+    """Error during connection establishment."""
+
+class SMTPHeloError(SMTPResponseException):
+    """The server refused our HELO reply."""
+
+class SMTPAuthenticationError(SMTPResponseException):
+    """Authentication error.
+
+    Most probably the server didn't accept the username/password
+    combination provided.
+    """
+
+def quoteaddr(addrstring):
+    """Quote a subset of the email addresses defined by RFC 821.
+
+    Should be able to handle anything email.utils.parseaddr can handle.
+    """
+    displayname, addr = email.utils.parseaddr(addrstring)
+    if (displayname, addr) == ('', ''):
+        # parseaddr couldn't parse it, use it as is and hope for the best.
+        if addrstring.strip().startswith('<'):
+            return addrstring
+        return "<%s>" % addrstring
+    return "<%s>" % addr
+
+def _addr_only(addrstring):
+    displayname, addr = email.utils.parseaddr(addrstring)
+    if (displayname, addr) == ('', ''):
+        # parseaddr couldn't parse it, so use it as is.
+        return addrstring
+    return addr
+
+# Legacy method kept for backward compatibility.
+def quotedata(data):
+    """Quote data for email.
+
+    Double leading '.', and change Unix newline '\\n', or Mac '\\r' into
+    internet CRLF end-of-line.
+    """
+    return re.sub(r'(?m)^\.', '..',
+                  re.sub(r'(?:\r\n|\n|\r(?!\n))', CRLF, data))
+
+def _quote_periods(bindata):
+    return re.sub(br'(?m)^\.', b'..', bindata)
+
+def _fix_eols(data):
+    return  re.sub(r'(?:\r\n|\n|\r(?!\n))', CRLF, data)
+
+try:
+    import ssl
+except ImportError:
+    _have_ssl = False
+else:
+    _have_ssl = True
+
+
+class SMTP:
+    """This class manages a connection to an SMTP or ESMTP server.
+    SMTP Objects:
+        SMTP objects have the following attributes:
+            helo_resp
+                This is the message given by the server in response to the
+                most recent HELO command.
+
+            ehlo_resp
+                This is the message given by the server in response to the
+                most recent EHLO command. This is usually multiline.
+
+            does_esmtp
+                This is a True value _after you do an EHLO command_, if the
+                server supports ESMTP.
+
+            esmtp_features
+                This is a dictionary, which, if the server supports ESMTP,
+                will _after you do an EHLO command_, contain the names of the
+                SMTP service extensions this server supports, and their
+                parameters (if any).
+
+                Note, all extension names are mapped to lower case in the
+                dictionary.
+
+        See each method's docstrings for details.  In general, there is a
+        method of the same name to perform each SMTP command.  There is also a
+        method called 'sendmail' that will do an entire mail transaction.
+        """
+    debuglevel = 0
+
+    sock = None
+    file = None
+    helo_resp = None
+    ehlo_msg = "ehlo"
+    ehlo_resp = None
+    does_esmtp = False
+    default_port = SMTP_PORT
+
+    def __init__(self, host='', port=0, local_hostname=None,
+                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
+                 source_address=None):
+        """Initialize a new instance.
+
+        If specified, `host` is the name of the remote host to which to
+        connect.  If specified, `port` specifies the port to which to connect.
+        By default, smtplib.SMTP_PORT is used.  If a host is specified the
+        connect method is called, and if it returns anything other than a
+        success code an SMTPConnectError is raised.  If specified,
+        `local_hostname` is used as the FQDN of the local host in the HELO/EHLO
+        command.  Otherwise, the local hostname is found using
+        socket.getfqdn(). The `source_address` parameter takes a 2-tuple (host,
+        port) for the socket to bind to as its source address before
+        connecting. If the host is '' and port is 0, the OS default behavior
+        will be used.
+
+        """
+        self._host = host
+        self.timeout = timeout
+        self.esmtp_features = {}
+        self.command_encoding = 'ascii'
+        self.source_address = source_address
+        self._auth_challenge_count = 0
+
+        if host:
+            (code, msg) = self.connect(host, port)
+            if code != 220:
+                self.close()
+                raise SMTPConnectError(code, msg)
+        if local_hostname is not None:
+            self.local_hostname = local_hostname
+        else:
+            # RFC 2821 says we should use the fqdn in the EHLO/HELO verb, and
+            # if that can't be calculated, that we should use a domain literal
+            # instead (essentially an encoded IP address like [A.B.C.D]).
+            fqdn = socket.getfqdn()
+            if '.' in fqdn:
+                self.local_hostname = fqdn
+            else:
+                # We can't find an fqdn hostname, so use a domain literal
+                addr = '127.0.0.1'
+                try:
+                    addr = socket.gethostbyname(socket.gethostname())
+                except socket.gaierror:
+                    pass
+                self.local_hostname = '[%s]' % addr
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *args):
+        try:
+            code, message = self.docmd("QUIT")
+            if code != 221:
+                raise SMTPResponseException(code, message)
+        except SMTPServerDisconnected:
+            pass
+        finally:
+            self.close()
+
+    def set_debuglevel(self, debuglevel):
+        """Set the debug output level.
+
+        A non-false value results in debug messages for connection and for all
+        messages sent to and received from the server.
+
+        """
+        self.debuglevel = debuglevel
+
+    def _print_debug(self, *args):
+        if self.debuglevel > 1:
+            print(datetime.datetime.now().time(), *args, file=sys.stderr)
+        else:
+            print(*args, file=sys.stderr)
+
+    def _get_socket(self, host, port, timeout):
+        # This makes it simpler for SMTP_SSL to use the SMTP connect code
+        # and just alter the socket connection bit.
+        if timeout is not None and not timeout:
+            raise ValueError('Non-blocking socket (timeout=0) is not supported')
+        if self.debuglevel > 0:
+            self._print_debug('connect: to', (host, port), self.source_address)
+        return socket.create_connection((host, port), timeout,
+                                        self.source_address)
+
+    def connect(self, host='localhost', port=0, source_address=None):
+        """Connect to a host on a given port.
+
+        If the hostname ends with a colon (`:') followed by a number, and
+        there is no port specified, that suffix will be stripped off and the
+        number interpreted as the port number to use.
+
+        Note: This method is automatically invoked by __init__, if a host is
+        specified during instantiation.
+
+        """
+
+        if source_address:
+            self.source_address = source_address
+
+        if not port and (host.find(':') == host.rfind(':')):
+            i = host.rfind(':')
+            if i >= 0:
+                host, port = host[:i], host[i + 1:]
+                try:
+                    port = int(port)
+                except ValueError:
+                    raise OSError("nonnumeric port")
+        if not port:
+            port = self.default_port
+        sys.audit("smtplib.connect", self, host, port)
+        self.sock = self._get_socket(host, port, self.timeout)
+        self.file = None
+        (code, msg) = self.getreply()
+        if self.debuglevel > 0:
+            self._print_debug('connect:', repr(msg))
+        return (code, msg)
+
+    def send(self, s):
+        """Send `s' to the server."""
+        if self.debuglevel > 0:
+            self._print_debug('send:', repr(s))
+        if self.sock:
+            if isinstance(s, str):
+                # send is used by the 'data' command, where command_encoding
+                # should not be used, but 'data' needs to convert the string to
+                # binary itself anyway, so that's not a problem.
+                s = s.encode(self.command_encoding)
+            sys.audit("smtplib.send", self, s)
+            try:
+                self.sock.sendall(s)
+            except OSError:
+                self.close()
+                raise SMTPServerDisconnected('Server not connected')
+        else:
+            raise SMTPServerDisconnected('please run connect() first')
+
+    def putcmd(self, cmd, args=""):
+        """Send a command to the server."""
+        if args == "":
+            s = cmd
+        else:
+            s = f'{cmd} {args}'
+        if '\r' in s or '\n' in s:
+            s = s.replace('\n', '\\n').replace('\r', '\\r')
+            raise ValueError(
+                f'command and arguments contain prohibited newline characters: {s}'
+            )
+        self.send(f'{s}{CRLF}')
+
+    def getreply(self):
+        """Get a reply from the server.
+
+        Returns a tuple consisting of:
+
+          - server response code (e.g. '250', or such, if all goes well)
+            Note: returns -1 if it can't read response code.
+
+          - server response string corresponding to response code (multiline
+            responses are converted to a single, multiline string).
+
+        Raises SMTPServerDisconnected if end-of-file is reached.
+        """
+        resp = []
+        if self.file is None:
+            self.file = self.sock.makefile('rb')
+        while 1:
+            try:
+                line = self.file.readline(_MAXLINE + 1)
+            except OSError as e:
+                self.close()
+                raise SMTPServerDisconnected("Connection unexpectedly closed: "
+                                             + str(e))
+            if not line:
+                self.close()
+                raise SMTPServerDisconnected("Connection unexpectedly closed")
+            if self.debuglevel > 0:
+                self._print_debug('reply:', repr(line))
+            if len(line) > _MAXLINE:
+                self.close()
+                raise SMTPResponseException(500, "Line too long.")
+            resp.append(line[4:].strip(b' \t\r\n'))
+            code = line[:3]
+            # Check that the error code is syntactically correct.
+            # Don't attempt to read a continuation line if it is broken.
+            try:
+                errcode = int(code)
+            except ValueError:
+                errcode = -1
+                break
+            # Check if multiline response.
+            if line[3:4] != b"-":
+                break
+
+        errmsg = b"\n".join(resp)
+        if self.debuglevel > 0:
+            self._print_debug('reply: retcode (%s); Msg: %a' % (errcode, errmsg))
+        return errcode, errmsg
+
+    def docmd(self, cmd, args=""):
+        """Send a command, and return its response code."""
+        self.putcmd(cmd, args)
+        return self.getreply()
+
+    # std smtp commands
+    def helo(self, name=''):
+        """SMTP 'helo' command.
+        Hostname to send for this command defaults to the FQDN of the local
+        host.
+        """
+        self.putcmd("helo", name or self.local_hostname)
+        (code, msg) = self.getreply()
+        self.helo_resp = msg
+        return (code, msg)
+
+    def ehlo(self, name=''):
+        """ SMTP 'ehlo' command.
+        Hostname to send for this command defaults to the FQDN of the local
+        host.
+        """
+        self.esmtp_features = {}
+        self.putcmd(self.ehlo_msg, name or self.local_hostname)
+        (code, msg) = self.getreply()
+        # According to RFC1869 some (badly written)
+        # MTA's will disconnect on an ehlo. Toss an exception if
+        # that happens -ddm
+        if code == -1 and len(msg) == 0:
+            self.close()
+            raise SMTPServerDisconnected("Server not connected")
+        self.ehlo_resp = msg
+        if code != 250:
+            return (code, msg)
+        self.does_esmtp = True
+        #parse the ehlo response -ddm
+        assert isinstance(self.ehlo_resp, bytes), repr(self.ehlo_resp)
+        resp = self.ehlo_resp.decode("latin-1").split('\n')
+        del resp[0]
+        for each in resp:
+            # To be able to communicate with as many SMTP servers as possible,
+            # we have to take the old-style auth advertisement into account,
+            # because:
+            # 1) Else our SMTP feature parser gets confused.
+            # 2) There are some servers that only advertise the auth methods we
+            #    support using the old style.
+            auth_match = OLDSTYLE_AUTH.match(each)
+            if auth_match:
+                # This doesn't remove duplicates, but that's no problem
+                self.esmtp_features["auth"] = self.esmtp_features.get("auth", "") \
+                                              + " " + auth_match.groups(0)[0]
+                continue
+
+            # RFC 1869 requires a space between ehlo keyword and parameters.
+            # It's actually stricter, in that only spaces are allowed between
+            # parameters, but were not going to check for that here.  Note
+            # that the space isn't present if there are no parameters.
+            m = re.match(r'(?P<feature>[A-Za-z0-9][A-Za-z0-9\-]*) ?', each)
+            if m:
+                feature = m.group("feature").lower()
+                params = m.string[m.end("feature"):].strip()
+                if feature == "auth":
+                    self.esmtp_features[feature] = self.esmtp_features.get(feature, "") \
+                                                   + " " + params
+                else:
+                    self.esmtp_features[feature] = params
+        return (code, msg)
+
+    def has_extn(self, opt):
+        """Does the server support a given SMTP service extension?"""
+        return opt.lower() in self.esmtp_features
+
+    def help(self, args=''):
+        """SMTP 'help' command.
+        Returns help text from server."""
+        self.putcmd("help", args)
+        return self.getreply()[1]
+
+    def rset(self):
+        """SMTP 'rset' command -- resets session."""
+        self.command_encoding = 'ascii'
+        return self.docmd("rset")
+
+    def _rset(self):
+        """Internal 'rset' command which ignores any SMTPServerDisconnected error.
+
+        Used internally in the library, since the server disconnected error
+        should appear to the application when the *next* command is issued, if
+        we are doing an internal "safety" reset.
+        """
+        try:
+            self.rset()
+        except SMTPServerDisconnected:
+            pass
+
+    def noop(self):
+        """SMTP 'noop' command -- doesn't do anything :>"""
+        return self.docmd("noop")
+
+    def mail(self, sender, options=()):
+        """SMTP 'mail' command -- begins mail xfer session.
+
+        This method may raise the following exceptions:
+
+         SMTPNotSupportedError  The options parameter includes 'SMTPUTF8'
+                                but the SMTPUTF8 extension is not supported by
+                                the server.
+        """
+        optionlist = ''
+        if options and self.does_esmtp:
+            if any(x.lower()=='smtputf8' for x in options):
+                if self.has_extn('smtputf8'):
+                    self.command_encoding = 'utf-8'
+                else:
+                    raise SMTPNotSupportedError(
+                        'SMTPUTF8 not supported by server')
+            optionlist = ' ' + ' '.join(options)
+        self.putcmd("mail", "FROM:%s%s" % (quoteaddr(sender), optionlist))
+        return self.getreply()
+
+    def rcpt(self, recip, options=()):
+        """SMTP 'rcpt' command -- indicates 1 recipient for this mail."""
+        optionlist = ''
+        if options and self.does_esmtp:
+            optionlist = ' ' + ' '.join(options)
+        self.putcmd("rcpt", "TO:%s%s" % (quoteaddr(recip), optionlist))
+        return self.getreply()
+
+    def data(self, msg):
+        """SMTP 'DATA' command -- sends message data to server.
+
+        Automatically quotes lines beginning with a period per rfc821.
+        Raises SMTPDataError if there is an unexpected reply to the
+        DATA command; the return value from this method is the final
+        response code received when the all data is sent.  If msg
+        is a string, lone '\\r' and '\\n' characters are converted to
+        '\\r\\n' characters.  If msg is bytes, it is transmitted as is.
+        """
+        self.putcmd("data")
+        (code, repl) = self.getreply()
+        if self.debuglevel > 0:
+            self._print_debug('data:', (code, repl))
+        if code != 354:
+            raise SMTPDataError(code, repl)
+        else:
+            if isinstance(msg, str):
+                msg = _fix_eols(msg).encode('ascii')
+            q = _quote_periods(msg)
+            if q[-2:] != bCRLF:
+                q = q + bCRLF
+            q = q + b"." + bCRLF
+            self.send(q)
+            (code, msg) = self.getreply()
+            if self.debuglevel > 0:
+                self._print_debug('data:', (code, msg))
+            return (code, msg)
+
+    def verify(self, address):
+        """SMTP 'verify' command -- checks for address validity."""
+        self.putcmd("vrfy", _addr_only(address))
+        return self.getreply()
+    # a.k.a.
+    vrfy = verify
+
+    def expn(self, address):
+        """SMTP 'expn' command -- expands a mailing list."""
+        self.putcmd("expn", _addr_only(address))
+        return self.getreply()
+
+    # some useful methods
+
+    def ehlo_or_helo_if_needed(self):
+        """Call self.ehlo() and/or self.helo() if needed.
+
+        If there has been no previous EHLO or HELO command this session, this
+        method tries ESMTP EHLO first.
+
+        This method may raise the following exceptions:
+
+         SMTPHeloError            The server didn't reply properly to
+                                  the helo greeting.
+        """
+        if self.helo_resp is None and self.ehlo_resp is None:
+            if not (200 <= self.ehlo()[0] <= 299):
+                (code, resp) = self.helo()
+                if not (200 <= code <= 299):
+                    raise SMTPHeloError(code, resp)
+
+    def auth(self, mechanism, authobject, *, initial_response_ok=True):
+        """Authentication command - requires response processing.
+
+        'mechanism' specifies which authentication mechanism is to
+        be used - the valid values are those listed in the 'auth'
+        element of 'esmtp_features'.
+
+        'authobject' must be a callable object taking a single argument:
+
+                data = authobject(challenge)
+
+        It will be called to process the server's challenge response; the
+        challenge argument it is passed will be a bytes.  It should return
+        an ASCII string that will be base64 encoded and sent to the server.
+
+        Keyword arguments:
+            - initial_response_ok: Allow sending the RFC 4954 initial-response
+              to the AUTH command, if the authentication methods supports it.
+        """
+        # RFC 4954 allows auth methods to provide an initial response.  Not all
+        # methods support it.  By definition, if they return something other
+        # than None when challenge is None, then they do.  See issue #15014.
+        mechanism = mechanism.upper()
+        initial_response = (authobject() if initial_response_ok else None)
+        if initial_response is not None:
+            response = encode_base64(initial_response.encode('ascii'), eol='')
+            (code, resp) = self.docmd("AUTH", mechanism + " " + response)
+            self._auth_challenge_count = 1
+        else:
+            (code, resp) = self.docmd("AUTH", mechanism)
+            self._auth_challenge_count = 0
+        # If server responds with a challenge, send the response.
+        while code == 334:
+            self._auth_challenge_count += 1
+            challenge = base64.decodebytes(resp)
+            response = encode_base64(
+                authobject(challenge).encode('ascii'), eol='')
+            (code, resp) = self.docmd(response)
+            # If server keeps sending challenges, something is wrong.
+            if self._auth_challenge_count > _MAXCHALLENGE:
+                raise SMTPException(
+                    "Server AUTH mechanism infinite loop. Last response: "
+                    + repr((code, resp))
+                )
+        if code in (235, 503):
+            return (code, resp)
+        raise SMTPAuthenticationError(code, resp)
+
+    def auth_cram_md5(self, challenge=None):
+        """ Authobject to use with CRAM-MD5 authentication. Requires self.user
+        and self.password to be set."""
+        # CRAM-MD5 does not support initial-response.
+        if challenge is None:
+            return None
+        return self.user + " " + hmac.HMAC(
+            self.password.encode('ascii'), challenge, 'md5').hexdigest()
+
+    def auth_plain(self, challenge=None):
+        """ Authobject to use with PLAIN authentication. Requires self.user and
+        self.password to be set."""
+        return "\0%s\0%s" % (self.user, self.password)
+
+    def auth_login(self, challenge=None):
+        """ Authobject to use with LOGIN authentication. Requires self.user and
+        self.password to be set."""
+        if challenge is None or self._auth_challenge_count < 2:
+            return self.user
+        else:
+            return self.password
+
+    def login(self, user, password, *, initial_response_ok=True):
+        """Log in on an SMTP server that requires authentication.
+
+        The arguments are:
+            - user:         The user name to authenticate with.
+            - password:     The password for the authentication.
+
+        Keyword arguments:
+            - initial_response_ok: Allow sending the RFC 4954 initial-response
+              to the AUTH command, if the authentication methods supports it.
+
+        If there has been no previous EHLO or HELO command this session, this
+        method tries ESMTP EHLO first.
+
+        This method will return normally if the authentication was successful.
+
+        This method may raise the following exceptions:
+
+         SMTPHeloError            The server didn't reply properly to
+                                  the helo greeting.
+         SMTPAuthenticationError  The server didn't accept the username/
+                                  password combination.
+         SMTPNotSupportedError    The AUTH command is not supported by the
+                                  server.
+         SMTPException            No suitable authentication method was
+                                  found.
+        """
+
+        self.ehlo_or_helo_if_needed()
+        if not self.has_extn("auth"):
+            raise SMTPNotSupportedError(
+                "SMTP AUTH extension not supported by server.")
+
+        # Authentication methods the server claims to support
+        advertised_authlist = self.esmtp_features["auth"].split()
+
+        # Authentication methods we can handle in our preferred order:
+        preferred_auths = ['CRAM-MD5', 'PLAIN', 'LOGIN']
+
+        # We try the supported authentications in our preferred order, if
+        # the server supports them.
+        authlist = [auth for auth in preferred_auths
+                    if auth in advertised_authlist]
+        if not authlist:
+            raise SMTPException("No suitable authentication method found.")
+
+        # Some servers advertise authentication methods they don't really
+        # support, so if authentication fails, we continue until we've tried
+        # all methods.
+        self.user, self.password = user, password
+        for authmethod in authlist:
+            method_name = 'auth_' + authmethod.lower().replace('-', '_')
+            try:
+                (code, resp) = self.auth(
+                    authmethod, getattr(self, method_name),
+                    initial_response_ok=initial_response_ok)
+                # 235 == 'Authentication successful'
+                # 503 == 'Error: already authenticated'
+                if code in (235, 503):
+                    return (code, resp)
+            except SMTPAuthenticationError as e:
+                last_exception = e
+
+        # We could not login successfully.  Return result of last attempt.
+        raise last_exception
+
+    def starttls(self, *, context=None):
+        """Puts the connection to the SMTP server into TLS mode.
+
+        If there has been no previous EHLO or HELO command this session, this
+        method tries ESMTP EHLO first.
+
+        If the server supports TLS, this will encrypt the rest of the SMTP
+        session. If you provide the context parameter,
+        the identity of the SMTP server and client can be checked. This,
+        however, depends on whether the socket module really checks the
+        certificates.
+
+        This method may raise the following exceptions:
+
+         SMTPHeloError            The server didn't reply properly to
+                                  the helo greeting.
+        """
+        self.ehlo_or_helo_if_needed()
+        if not self.has_extn("starttls"):
+            raise SMTPNotSupportedError(
+                "STARTTLS extension not supported by server.")
+        (resp, reply) = self.docmd("STARTTLS")
+        if resp == 220:
+            if not _have_ssl:
+                raise RuntimeError("No SSL support included in this Python")
+            if context is None:
+                context = ssl._create_stdlib_context()
+            self.sock = context.wrap_socket(self.sock,
+                                            server_hostname=self._host)
+            self.file = None
+            # RFC 3207:
+            # The client MUST discard any knowledge obtained from
+            # the server, such as the list of SMTP service extensions,
+            # which was not obtained from the TLS negotiation itself.
+            self.helo_resp = None
+            self.ehlo_resp = None
+            self.esmtp_features = {}
+            self.does_esmtp = False
+        else:
+            # RFC 3207:
+            # 501 Syntax error (no parameters allowed)
+            # 454 TLS not available due to temporary reason
+            raise SMTPResponseException(resp, reply)
+        return (resp, reply)
+
+    def sendmail(self, from_addr, to_addrs, msg, mail_options=(),
+                 rcpt_options=()):
+        """This command performs an entire mail transaction.
+
+        The arguments are:
+            - from_addr    : The address sending this mail.
+            - to_addrs     : A list of addresses to send this mail to.  A bare
+                             string will be treated as a list with 1 address.
+            - msg          : The message to send.
+            - mail_options : List of ESMTP options (such as 8bitmime) for the
+                             mail command.
+            - rcpt_options : List of ESMTP options (such as DSN commands) for
+                             all the rcpt commands.
+
+        msg may be a string containing characters in the ASCII range, or a byte
+        string.  A string is encoded to bytes using the ascii codec, and lone
+        \\r and \\n characters are converted to \\r\\n characters.
+
+        If there has been no previous EHLO or HELO command this session, this
+        method tries ESMTP EHLO first.  If the server does ESMTP, message size
+        and each of the specified options will be passed to it.  If EHLO
+        fails, HELO will be tried and ESMTP options suppressed.
+
+        This method will return normally if the mail is accepted for at least
+        one recipient.  It returns a dictionary, with one entry for each
+        recipient that was refused.  Each entry contains a tuple of the SMTP
+        error code and the accompanying error message sent by the server.
+
+        This method may raise the following exceptions:
+
+         SMTPHeloError          The server didn't reply properly to
+                                the helo greeting.
+         SMTPRecipientsRefused  The server rejected ALL recipients
+                                (no mail was sent).
+         SMTPSenderRefused      The server didn't accept the from_addr.
+         SMTPDataError          The server replied with an unexpected
+                                error code (other than a refusal of
+                                a recipient).
+         SMTPNotSupportedError  The mail_options parameter includes 'SMTPUTF8'
+                                but the SMTPUTF8 extension is not supported by
+                                the server.
+
+        Note: the connection will be open even after an exception is raised.
+
+        Example:
+
+         >>> import smtplib
+         >>> s=smtplib.SMTP("localhost")
+         >>> tolist=["one@one.org","two@two.org","three@three.org","four@four.org"]
+         >>> msg = '''\\
+         ... From: Me@my.org
+         ... Subject: testin'...
+         ...
+         ... This is a test '''
+         >>> s.sendmail("me@my.org",tolist,msg)
+         { "three@three.org" : ( 550 ,"User unknown" ) }
+         >>> s.quit()
+
+        In the above example, the message was accepted for delivery to three
+        of the four addresses, and one was rejected, with the error code
+        550.  If all addresses are accepted, then the method will return an
+        empty dictionary.
+
+        """
+        self.ehlo_or_helo_if_needed()
+        esmtp_opts = []
+        if isinstance(msg, str):
+            msg = _fix_eols(msg).encode('ascii')
+        if self.does_esmtp:
+            if self.has_extn('size'):
+                esmtp_opts.append("size=%d" % len(msg))
+            for option in mail_options:
+                esmtp_opts.append(option)
+        (code, resp) = self.mail(from_addr, esmtp_opts)
+        if code != 250:
+            if code == 421:
+                self.close()
+            else:
+                self._rset()
+            raise SMTPSenderRefused(code, resp, from_addr)
+        senderrs = {}
+        if isinstance(to_addrs, str):
+            to_addrs = [to_addrs]
+        for each in to_addrs:
+            (code, resp) = self.rcpt(each, rcpt_options)
+            if (code != 250) and (code != 251):
+                senderrs[each] = (code, resp)
+            if code == 421:
+                self.close()
+                raise SMTPRecipientsRefused(senderrs)
+        if len(senderrs) == len(to_addrs):
+            # the server refused all our recipients
+            self._rset()
+            raise SMTPRecipientsRefused(senderrs)
+        (code, resp) = self.data(msg)
+        if code != 250:
+            if code == 421:
+                self.close()
+            else:
+                self._rset()
+            raise SMTPDataError(code, resp)
+        #if we got here then somebody got our mail
+        return senderrs
+
+    def send_message(self, msg, from_addr=None, to_addrs=None,
+                     mail_options=(), rcpt_options=()):
+        """Converts message to a bytestring and passes it to sendmail.
+
+        The arguments are as for sendmail, except that msg is an
+        email.message.Message object.  If from_addr is None or to_addrs is
+        None, these arguments are taken from the headers of the Message as
+        described in RFC 2822 (a ValueError is raised if there is more than
+        one set of 'Resent-' headers).  Regardless of the values of from_addr and
+        to_addr, any Bcc field (or Resent-Bcc field, when the Message is a
+        resent) of the Message object won't be transmitted.  The Message
+        object is then serialized using email.generator.BytesGenerator and
+        sendmail is called to transmit the message.  If the sender or any of
+        the recipient addresses contain non-ASCII and the server advertises the
+        SMTPUTF8 capability, the policy is cloned with utf8 set to True for the
+        serialization, and SMTPUTF8 and BODY=8BITMIME are asserted on the send.
+        If the server does not support SMTPUTF8, an SMTPNotSupported error is
+        raised.  Otherwise the generator is called without modifying the
+        policy.
+
+        """
+        # 'Resent-Date' is a mandatory field if the Message is resent (RFC 2822
+        # Section 3.6.6). In such a case, we use the 'Resent-*' fields.  However,
+        # if there is more than one 'Resent-' block there's no way to
+        # unambiguously determine which one is the most recent in all cases,
+        # so rather than guess we raise a ValueError in that case.
+        #
+        # TODO implement heuristics to guess the correct Resent-* block with an
+        # option allowing the user to enable the heuristics.  (It should be
+        # possible to guess correctly almost all of the time.)
+
+        self.ehlo_or_helo_if_needed()
+        resent = msg.get_all('Resent-Date')
+        if resent is None:
+            header_prefix = ''
+        elif len(resent) == 1:
+            header_prefix = 'Resent-'
+        else:
+            raise ValueError("message has more than one 'Resent-' header block")
+        if from_addr is None:
+            # Prefer the sender field per RFC 2822:3.6.2.
+            from_addr = (msg[header_prefix + 'Sender']
+                         if (header_prefix + 'Sender') in msg
+                         else msg[header_prefix + 'From'])
+            from_addr = email.utils.getaddresses([from_addr])[0][1]
+        if to_addrs is None:
+            addr_fields = [f for f in (msg[header_prefix + 'To'],
+                                       msg[header_prefix + 'Bcc'],
+                                       msg[header_prefix + 'Cc'])
+                           if f is not None]
+            to_addrs = [a[1] for a in email.utils.getaddresses(addr_fields)]
+        # Make a local copy so we can delete the bcc headers.
+        msg_copy = copy.copy(msg)
+        del msg_copy['Bcc']
+        del msg_copy['Resent-Bcc']
+        international = False
+        try:
+            ''.join([from_addr, *to_addrs]).encode('ascii')
+        except UnicodeEncodeError:
+            if not self.has_extn('smtputf8'):
+                raise SMTPNotSupportedError(
+                    "One or more source or delivery addresses require"
+                    " internationalized email support, but the server"
+                    " does not advertise the required SMTPUTF8 capability")
+            international = True
+        with io.BytesIO() as bytesmsg:
+            if international:
+                g = email.generator.BytesGenerator(
+                    bytesmsg, policy=msg.policy.clone(utf8=True))
+                mail_options = (*mail_options, 'SMTPUTF8', 'BODY=8BITMIME')
+            else:
+                g = email.generator.BytesGenerator(bytesmsg)
+            g.flatten(msg_copy, linesep='\r\n')
+            flatmsg = bytesmsg.getvalue()
+        return self.sendmail(from_addr, to_addrs, flatmsg, mail_options,
+                             rcpt_options)
+
+    def close(self):
+        """Close the connection to the SMTP server."""
+        try:
+            file = self.file
+            self.file = None
+            if file:
+                file.close()
+        finally:
+            sock = self.sock
+            self.sock = None
+            if sock:
+                sock.close()
+
+    def quit(self):
+        """Terminate the SMTP session."""
+        res = self.docmd("quit")
+        # A new EHLO is required after reconnecting with connect()
+        self.ehlo_resp = self.helo_resp = None
+        self.esmtp_features = {}
+        self.does_esmtp = False
+        self.close()
+        return res
+
+if _have_ssl:
+
+    class SMTP_SSL(SMTP):
+        """ This is a subclass derived from SMTP that connects over an SSL
+        encrypted socket (to use this class you need a socket module that was
+        compiled with SSL support). If host is not specified, '' (the local
+        host) is used. If port is omitted, the standard SMTP-over-SSL port
+        (465) is used.  local_hostname and source_address have the same meaning
+        as they do in the SMTP class.  context also optional, can contain a
+        SSLContext.
+
+        """
+
+        default_port = SMTP_SSL_PORT
+
+        def __init__(self, host='', port=0, local_hostname=None,
+                     *, timeout=socket._GLOBAL_DEFAULT_TIMEOUT,
+                     source_address=None, context=None):
+            if context is None:
+                context = ssl._create_stdlib_context()
+            self.context = context
+            SMTP.__init__(self, host, port, local_hostname, timeout,
+                          source_address)
+
+        def _get_socket(self, host, port, timeout):
+            if self.debuglevel > 0:
+                self._print_debug('connect:', (host, port))
+            new_socket = super()._get_socket(host, port, timeout)
+            new_socket = self.context.wrap_socket(new_socket,
+                                                  server_hostname=self._host)
+            return new_socket
+
+    __all__.append("SMTP_SSL")
+
+#
+# LMTP extension
+#
+LMTP_PORT = 2003
+
+class LMTP(SMTP):
+    """LMTP - Local Mail Transfer Protocol
+
+    The LMTP protocol, which is very similar to ESMTP, is heavily based
+    on the standard SMTP client. It's common to use Unix sockets for
+    LMTP, so our connect() method must support that as well as a regular
+    host:port server.  local_hostname and source_address have the same
+    meaning as they do in the SMTP class.  To specify a Unix socket,
+    you must use an absolute path as the host, starting with a '/'.
+
+    Authentication is supported, using the regular SMTP mechanism. When
+    using a Unix socket, LMTP generally don't support or require any
+    authentication, but your mileage might vary."""
+
+    ehlo_msg = "lhlo"
+
+    def __init__(self, host='', port=LMTP_PORT, local_hostname=None,
+                 source_address=None, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+        """Initialize a new instance."""
+        super().__init__(host, port, local_hostname=local_hostname,
+                         source_address=source_address, timeout=timeout)
+
+    def connect(self, host='localhost', port=0, source_address=None):
+        """Connect to the LMTP daemon, on either a Unix or a TCP socket."""
+        if host[0] != '/':
+            return super().connect(host, port, source_address=source_address)
+
+        if self.timeout is not None and not self.timeout:
+            raise ValueError('Non-blocking socket (timeout=0) is not supported')
+
+        # Handle Unix-domain sockets.
+        try:
+            self.sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
+            if self.timeout is not socket._GLOBAL_DEFAULT_TIMEOUT:
+                self.sock.settimeout(self.timeout)
+            self.file = None
+            self.sock.connect(host)
+        except OSError:
+            if self.debuglevel > 0:
+                self._print_debug('connect fail:', host)
+            if self.sock:
+                self.sock.close()
+            self.sock = None
+            raise
+        (code, msg) = self.getreply()
+        if self.debuglevel > 0:
+            self._print_debug('connect:', msg)
+        return (code, msg)
+
+
+# Test the sendmail method, which tests most of the others.
+# Note: This always sends to localhost.
+if __name__ == '__main__':
+    def prompt(prompt):
+        sys.stdout.write(prompt + ": ")
+        sys.stdout.flush()
+        return sys.stdin.readline().strip()
+
+    fromaddr = prompt("From")
+    toaddrs = prompt("To").split(',')
+    print("Enter message, end with ^D:")
+    msg = ''
+    while line := sys.stdin.readline():
+        msg = msg + line
+    print("Message length is %d" % len(msg))
+
+    server = SMTP('localhost')
+    server.set_debuglevel(1)
+    server.sendmail(fromaddr, toaddrs, msg)
+    server.quit()
diff --git a/Lib/test/ieee754.txt b/Lib/test/ieee754.txt
new file mode 100644
index 0000000000..3e986cdb10
--- /dev/null
+++ b/Lib/test/ieee754.txt
@@ -0,0 +1,183 @@
+======================================
+Python IEEE 754 floating point support
+======================================
+
+>>> from sys import float_info as FI
+>>> from math import *
+>>> PI = pi
+>>> E = e
+
+You must never compare two floats with == because you are not going to get
+what you expect. We treat two floats as equal if the difference between them
+is small than epsilon.
+>>> EPS = 1E-15
+>>> def equal(x, y):
+...     """Almost equal helper for floats"""
+...     return abs(x - y) < EPS
+
+
+NaNs and INFs
+=============
+
+In Python 2.6 and newer NaNs (not a number) and infinity can be constructed
+from the strings 'inf' and 'nan'.
+
+>>> INF = float('inf')
+>>> NINF = float('-inf')
+>>> NAN = float('nan')
+
+>>> INF
+inf
+>>> NINF
+-inf
+>>> NAN
+nan
+
+The math module's ``isnan`` and ``isinf`` functions can be used to detect INF
+and NAN:
+>>> isinf(INF), isinf(NINF), isnan(NAN)
+(True, True, True)
+>>> INF == -NINF
+True
+
+Infinity
+--------
+
+Ambiguous operations like ``0 * inf`` or ``inf - inf`` result in NaN.
+>>> INF * 0
+nan
+>>> INF - INF
+nan
+>>> INF / INF
+nan
+
+However unambiguous operations with inf return inf:
+>>> INF * INF
+inf
+>>> 1.5 * INF
+inf
+>>> 0.5 * INF
+inf
+>>> INF / 1000
+inf
+
+Not a Number
+------------
+
+NaNs are never equal to another number, even itself
+>>> NAN == NAN
+False
+>>> NAN < 0
+False
+>>> NAN >= 0
+False
+
+All operations involving a NaN return a NaN except for nan**0 and 1**nan.
+>>> 1 + NAN
+nan
+>>> 1 * NAN
+nan
+>>> 0 * NAN
+nan
+>>> 1 ** NAN
+1.0
+>>> NAN ** 0
+1.0
+>>> 0 ** NAN
+nan
+>>> (1.0 + FI.epsilon) * NAN
+nan
+
+Misc Functions
+==============
+
+The power of 1 raised to x is always 1.0, even for special values like 0,
+infinity and NaN.
+
+>>> pow(1, 0)
+1.0
+>>> pow(1, INF)
+1.0
+>>> pow(1, -INF)
+1.0
+>>> pow(1, NAN)
+1.0
+
+The power of 0 raised to x is defined as 0, if x is positive. Negative
+finite values are a domain error or zero division error and NaN result in a
+silent NaN.
+
+>>> pow(0, 0)
+1.0
+>>> pow(0, INF)
+0.0
+>>> pow(0, -INF)
+inf
+>>> 0 ** -1
+Traceback (most recent call last):
+...
+ZeroDivisionError: 0.0 cannot be raised to a negative power
+>>> pow(0, NAN)
+nan
+
+
+Trigonometric Functions
+=======================
+
+>>> sin(INF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> sin(NINF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> sin(NAN)
+nan
+>>> cos(INF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> cos(NINF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> cos(NAN)
+nan
+>>> tan(INF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> tan(NINF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> tan(NAN)
+nan
+
+Neither pi nor tan are exact, but you can assume that tan(pi/2) is a large value
+and tan(pi) is a very small value:
+>>> tan(PI/2) > 1E10
+True
+>>> -tan(-PI/2) > 1E10
+True
+>>> tan(PI) < 1E-15
+True
+
+>>> asin(NAN), acos(NAN), atan(NAN)
+(nan, nan, nan)
+>>> asin(INF), asin(NINF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> acos(INF), acos(NINF)
+Traceback (most recent call last):
+...
+ValueError: math domain error
+>>> equal(atan(INF), PI/2), equal(atan(NINF), -PI/2)
+(True, True)
+
+
+Hyberbolic Functions
+====================
+
diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index a1a6bd8e73..1efe5bddb1 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -400,33 +400,37 @@ def skip_if_buildbot(reason=None):
         isbuildbot = False
     return unittest.skipIf(isbuildbot, reason)
 
-def check_sanitizer(*, address=False, memory=False, ub=False):
+def check_sanitizer(*, address=False, memory=False, ub=False, thread=False):
     """Returns True if Python is compiled with sanitizer support"""
-    if not (address or memory or ub):
-        raise ValueError('At least one of address, memory, or ub must be True')
+    if not (address or memory or ub or thread):
+        raise ValueError('At least one of address, memory, ub or thread must be True')
 
 
-    _cflags = sysconfig.get_config_var('CFLAGS') or ''
-    _config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
+    cflags = sysconfig.get_config_var('CFLAGS') or ''
+    config_args = sysconfig.get_config_var('CONFIG_ARGS') or ''
     memory_sanitizer = (
-        '-fsanitize=memory' in _cflags or
-        '--with-memory-sanitizer' in _config_args
+            '-fsanitize=memory' in cflags or
+            '--with-memory-sanitizer' in config_args
     )
     address_sanitizer = (
-        '-fsanitize=address' in _cflags or
-        '--with-address-sanitizer' in _config_args
+            '-fsanitize=address' in cflags or
+            '--with-address-sanitizer' in config_args
     )
     ub_sanitizer = (
-        '-fsanitize=undefined' in _cflags or
-        '--with-undefined-behavior-sanitizer' in _config_args
+            '-fsanitize=undefined' in cflags or
+            '--with-undefined-behavior-sanitizer' in config_args
+    )
+    thread_sanitizer = (
+            '-fsanitize=thread' in cflags or
+            '--with-thread-sanitizer' in config_args
     )
     return (
-        (memory and memory_sanitizer) or
-        (address and address_sanitizer) or
-        (ub and ub_sanitizer)
+            (memory and memory_sanitizer) or
+            (address and address_sanitizer) or
+            (ub and ub_sanitizer) or
+            (thread and thread_sanitizer)
     )
 
-
 def skip_if_sanitizer(reason=None, *, address=False, memory=False, ub=False, thread=False):
     """Decorator raising SkipTest if running with a sanitizer active."""
     if not reason:
@@ -2550,3 +2554,21 @@ def adjust_int_max_str_digits(max_digits):
 #Windows doesn't have os.uname() but it doesn't support s390x.
 skip_on_s390x = unittest.skipIf(hasattr(os, 'uname') and os.uname().machine == 's390x',
                                 'skipped on s390x')
+HAVE_ASAN_FORK_BUG = check_sanitizer(address=True)
+
+# From python 3.12.8
+class BrokenIter:
+    def __init__(self, init_raises=False, next_raises=False, iter_raises=False):
+        if init_raises:
+            1/0
+        self.next_raises = next_raises
+        self.iter_raises = iter_raises
+
+    def __next__(self):
+        if self.next_raises:
+            1/0
+
+    def __iter__(self):
+        if self.iter_raises:
+            1/0
+        return self
diff --git a/Lib/test/support/smtpd.py b/Lib/test/support/smtpd.py
new file mode 100644
index 0000000000..ec4e7d2f4c
--- /dev/null
+++ b/Lib/test/support/smtpd.py
@@ -0,0 +1,873 @@
+#! /usr/bin/env python3
+"""An RFC 5321 smtp proxy with optional RFC 1870 and RFC 6531 extensions.
+
+Usage: %(program)s [options] [localhost:localport [remotehost:remoteport]]
+
+Options:
+
+    --nosetuid
+    -n
+        This program generally tries to setuid `nobody', unless this flag is
+        set.  The setuid call will fail if this program is not run as root (in
+        which case, use this flag).
+
+    --version
+    -V
+        Print the version number and exit.
+
+    --class classname
+    -c classname
+        Use `classname' as the concrete SMTP proxy class.  Uses `PureProxy' by
+        default.
+
+    --size limit
+    -s limit
+        Restrict the total size of the incoming message to "limit" number of
+        bytes via the RFC 1870 SIZE extension.  Defaults to 33554432 bytes.
+
+    --smtputf8
+    -u
+        Enable the SMTPUTF8 extension and behave as an RFC 6531 smtp proxy.
+
+    --debug
+    -d
+        Turn on debugging prints.
+
+    --help
+    -h
+        Print this message and exit.
+
+Version: %(__version__)s
+
+If localhost is not given then `localhost' is used, and if localport is not
+given then 8025 is used.  If remotehost is not given then `localhost' is used,
+and if remoteport is not given, then 25 is used.
+"""
+
+# Overview:
+#
+# This file implements the minimal SMTP protocol as defined in RFC 5321.  It
+# has a hierarchy of classes which implement the backend functionality for the
+# smtpd.  A number of classes are provided:
+#
+#   SMTPServer - the base class for the backend.  Raises NotImplementedError
+#   if you try to use it.
+#
+#   DebuggingServer - simply prints each message it receives on stdout.
+#
+#   PureProxy - Proxies all messages to a real smtpd which does final
+#   delivery.  One known problem with this class is that it doesn't handle
+#   SMTP errors from the backend server at all.  This should be fixed
+#   (contributions are welcome!).
+#
+#
+# Author: Barry Warsaw <barry@python.org>
+#
+# TODO:
+#
+# - support mailbox delivery
+# - alias files
+# - Handle more ESMTP extensions
+# - handle error codes from the backend smtpd
+
+import sys
+import os
+import errno
+import getopt
+import time
+import socket
+import collections
+from test.support import asyncore, asynchat
+from warnings import warn
+from email._header_value_parser import get_addr_spec, get_angle_addr
+
+__all__ = [
+    "SMTPChannel", "SMTPServer", "DebuggingServer", "PureProxy",
+]
+
+program = sys.argv[0]
+__version__ = 'Python SMTP proxy version 0.3'
+
+
+class Devnull:
+    def write(self, msg): pass
+    def flush(self): pass
+
+
+DEBUGSTREAM = Devnull()
+NEWLINE = '\n'
+COMMASPACE = ', '
+DATA_SIZE_DEFAULT = 33554432
+
+
+def usage(code, msg=''):
+    print(__doc__ % globals(), file=sys.stderr)
+    if msg:
+        print(msg, file=sys.stderr)
+    sys.exit(code)
+
+
+class SMTPChannel(asynchat.async_chat):
+    COMMAND = 0
+    DATA = 1
+
+    command_size_limit = 512
+    command_size_limits = collections.defaultdict(lambda x=command_size_limit: x)
+
+    @property
+    def max_command_size_limit(self):
+        try:
+            return max(self.command_size_limits.values())
+        except ValueError:
+            return self.command_size_limit
+
+    def __init__(self, server, conn, addr, data_size_limit=DATA_SIZE_DEFAULT,
+                 map=None, enable_SMTPUTF8=False, decode_data=False):
+        asynchat.async_chat.__init__(self, conn, map=map)
+        self.smtp_server = server
+        self.conn = conn
+        self.addr = addr
+        self.data_size_limit = data_size_limit
+        self.enable_SMTPUTF8 = enable_SMTPUTF8
+        self._decode_data = decode_data
+        if enable_SMTPUTF8 and decode_data:
+            raise ValueError("decode_data and enable_SMTPUTF8 cannot"
+                             " be set to True at the same time")
+        if decode_data:
+            self._emptystring = ''
+            self._linesep = '\r\n'
+            self._dotsep = '.'
+            self._newline = NEWLINE
+        else:
+            self._emptystring = b''
+            self._linesep = b'\r\n'
+            self._dotsep = ord(b'.')
+            self._newline = b'\n'
+        self._set_rset_state()
+        self.seen_greeting = ''
+        self.extended_smtp = False
+        self.command_size_limits.clear()
+        self.fqdn = socket.getfqdn()
+        try:
+            self.peer = conn.getpeername()
+        except OSError as err:
+            # a race condition  may occur if the other end is closing
+            # before we can get the peername
+            self.close()
+            if err.errno != errno.ENOTCONN:
+                raise
+            return
+        print('Peer:', repr(self.peer), file=DEBUGSTREAM)
+        self.push('220 %s %s' % (self.fqdn, __version__))
+
+    def _set_post_data_state(self):
+        """Reset state variables to their post-DATA state."""
+        self.smtp_state = self.COMMAND
+        self.mailfrom = None
+        self.rcpttos = []
+        self.require_SMTPUTF8 = False
+        self.num_bytes = 0
+        self.set_terminator(b'\r\n')
+
+    def _set_rset_state(self):
+        """Reset all state variables except the greeting."""
+        self._set_post_data_state()
+        self.received_data = ''
+        self.received_lines = []
+
+
+    # properties for backwards-compatibility
+    @property
+    def __server(self):
+        warn("Access to __server attribute on SMTPChannel is deprecated, "
+             "use 'smtp_server' instead", DeprecationWarning, 2)
+        return self.smtp_server
+    @__server.setter
+    def __server(self, value):
+        warn("Setting __server attribute on SMTPChannel is deprecated, "
+             "set 'smtp_server' instead", DeprecationWarning, 2)
+        self.smtp_server = value
+
+    @property
+    def __line(self):
+        warn("Access to __line attribute on SMTPChannel is deprecated, "
+             "use 'received_lines' instead", DeprecationWarning, 2)
+        return self.received_lines
+    @__line.setter
+    def __line(self, value):
+        warn("Setting __line attribute on SMTPChannel is deprecated, "
+             "set 'received_lines' instead", DeprecationWarning, 2)
+        self.received_lines = value
+
+    @property
+    def __state(self):
+        warn("Access to __state attribute on SMTPChannel is deprecated, "
+             "use 'smtp_state' instead", DeprecationWarning, 2)
+        return self.smtp_state
+    @__state.setter
+    def __state(self, value):
+        warn("Setting __state attribute on SMTPChannel is deprecated, "
+             "set 'smtp_state' instead", DeprecationWarning, 2)
+        self.smtp_state = value
+
+    @property
+    def __greeting(self):
+        warn("Access to __greeting attribute on SMTPChannel is deprecated, "
+             "use 'seen_greeting' instead", DeprecationWarning, 2)
+        return self.seen_greeting
+    @__greeting.setter
+    def __greeting(self, value):
+        warn("Setting __greeting attribute on SMTPChannel is deprecated, "
+             "set 'seen_greeting' instead", DeprecationWarning, 2)
+        self.seen_greeting = value
+
+    @property
+    def __mailfrom(self):
+        warn("Access to __mailfrom attribute on SMTPChannel is deprecated, "
+             "use 'mailfrom' instead", DeprecationWarning, 2)
+        return self.mailfrom
+    @__mailfrom.setter
+    def __mailfrom(self, value):
+        warn("Setting __mailfrom attribute on SMTPChannel is deprecated, "
+             "set 'mailfrom' instead", DeprecationWarning, 2)
+        self.mailfrom = value
+
+    @property
+    def __rcpttos(self):
+        warn("Access to __rcpttos attribute on SMTPChannel is deprecated, "
+             "use 'rcpttos' instead", DeprecationWarning, 2)
+        return self.rcpttos
+    @__rcpttos.setter
+    def __rcpttos(self, value):
+        warn("Setting __rcpttos attribute on SMTPChannel is deprecated, "
+             "set 'rcpttos' instead", DeprecationWarning, 2)
+        self.rcpttos = value
+
+    @property
+    def __data(self):
+        warn("Access to __data attribute on SMTPChannel is deprecated, "
+             "use 'received_data' instead", DeprecationWarning, 2)
+        return self.received_data
+    @__data.setter
+    def __data(self, value):
+        warn("Setting __data attribute on SMTPChannel is deprecated, "
+             "set 'received_data' instead", DeprecationWarning, 2)
+        self.received_data = value
+
+    @property
+    def __fqdn(self):
+        warn("Access to __fqdn attribute on SMTPChannel is deprecated, "
+             "use 'fqdn' instead", DeprecationWarning, 2)
+        return self.fqdn
+    @__fqdn.setter
+    def __fqdn(self, value):
+        warn("Setting __fqdn attribute on SMTPChannel is deprecated, "
+             "set 'fqdn' instead", DeprecationWarning, 2)
+        self.fqdn = value
+
+    @property
+    def __peer(self):
+        warn("Access to __peer attribute on SMTPChannel is deprecated, "
+             "use 'peer' instead", DeprecationWarning, 2)
+        return self.peer
+    @__peer.setter
+    def __peer(self, value):
+        warn("Setting __peer attribute on SMTPChannel is deprecated, "
+             "set 'peer' instead", DeprecationWarning, 2)
+        self.peer = value
+
+    @property
+    def __conn(self):
+        warn("Access to __conn attribute on SMTPChannel is deprecated, "
+             "use 'conn' instead", DeprecationWarning, 2)
+        return self.conn
+    @__conn.setter
+    def __conn(self, value):
+        warn("Setting __conn attribute on SMTPChannel is deprecated, "
+             "set 'conn' instead", DeprecationWarning, 2)
+        self.conn = value
+
+    @property
+    def __addr(self):
+        warn("Access to __addr attribute on SMTPChannel is deprecated, "
+             "use 'addr' instead", DeprecationWarning, 2)
+        return self.addr
+    @__addr.setter
+    def __addr(self, value):
+        warn("Setting __addr attribute on SMTPChannel is deprecated, "
+             "set 'addr' instead", DeprecationWarning, 2)
+        self.addr = value
+
+    # Overrides base class for convenience.
+    def push(self, msg):
+        asynchat.async_chat.push(self, bytes(
+            msg + '\r\n', 'utf-8' if self.require_SMTPUTF8 else 'ascii'))
+
+    # Implementation of base class abstract method
+    def collect_incoming_data(self, data):
+        limit = None
+        if self.smtp_state == self.COMMAND:
+            limit = self.max_command_size_limit
+        elif self.smtp_state == self.DATA:
+            limit = self.data_size_limit
+        if limit and self.num_bytes > limit:
+            return
+        elif limit:
+            self.num_bytes += len(data)
+        if self._decode_data:
+            self.received_lines.append(str(data, 'utf-8'))
+        else:
+            self.received_lines.append(data)
+
+    # Implementation of base class abstract method
+    def found_terminator(self):
+        line = self._emptystring.join(self.received_lines)
+        print('Data:', repr(line), file=DEBUGSTREAM)
+        self.received_lines = []
+        if self.smtp_state == self.COMMAND:
+            sz, self.num_bytes = self.num_bytes, 0
+            if not line:
+                self.push('500 Error: bad syntax')
+                return
+            if not self._decode_data:
+                line = str(line, 'utf-8')
+            i = line.find(' ')
+            if i < 0:
+                command = line.upper()
+                arg = None
+            else:
+                command = line[:i].upper()
+                arg = line[i+1:].strip()
+            max_sz = (self.command_size_limits[command]
+                      if self.extended_smtp else self.command_size_limit)
+            if sz > max_sz:
+                self.push('500 Error: line too long')
+                return
+            method = getattr(self, 'smtp_' + command, None)
+            if not method:
+                self.push('500 Error: command "%s" not recognized' % command)
+                return
+            method(arg)
+            return
+        else:
+            if self.smtp_state != self.DATA:
+                self.push('451 Internal confusion')
+                self.num_bytes = 0
+                return
+            if self.data_size_limit and self.num_bytes > self.data_size_limit:
+                self.push('552 Error: Too much mail data')
+                self.num_bytes = 0
+                return
+            # Remove extraneous carriage returns and de-transparency according
+            # to RFC 5321, Section 4.5.2.
+            data = []
+            for text in line.split(self._linesep):
+                if text and text[0] == self._dotsep:
+                    data.append(text[1:])
+                else:
+                    data.append(text)
+            self.received_data = self._newline.join(data)
+            args = (self.peer, self.mailfrom, self.rcpttos, self.received_data)
+            kwargs = {}
+            if not self._decode_data:
+                kwargs = {
+                    'mail_options': self.mail_options,
+                    'rcpt_options': self.rcpt_options,
+                }
+            status = self.smtp_server.process_message(*args, **kwargs)
+            self._set_post_data_state()
+            if not status:
+                self.push('250 OK')
+            else:
+                self.push(status)
+
+    # SMTP and ESMTP commands
+    def smtp_HELO(self, arg):
+        if not arg:
+            self.push('501 Syntax: HELO hostname')
+            return
+        # See issue #21783 for a discussion of this behavior.
+        if self.seen_greeting:
+            self.push('503 Duplicate HELO/EHLO')
+            return
+        self._set_rset_state()
+        self.seen_greeting = arg
+        self.push('250 %s' % self.fqdn)
+
+    def smtp_EHLO(self, arg):
+        if not arg:
+            self.push('501 Syntax: EHLO hostname')
+            return
+        # See issue #21783 for a discussion of this behavior.
+        if self.seen_greeting:
+            self.push('503 Duplicate HELO/EHLO')
+            return
+        self._set_rset_state()
+        self.seen_greeting = arg
+        self.extended_smtp = True
+        self.push('250-%s' % self.fqdn)
+        if self.data_size_limit:
+            self.push('250-SIZE %s' % self.data_size_limit)
+            self.command_size_limits['MAIL'] += 26
+        if not self._decode_data:
+            self.push('250-8BITMIME')
+        if self.enable_SMTPUTF8:
+            self.push('250-SMTPUTF8')
+            self.command_size_limits['MAIL'] += 10
+        self.push('250 HELP')
+
+    def smtp_NOOP(self, arg):
+        if arg:
+            self.push('501 Syntax: NOOP')
+        else:
+            self.push('250 OK')
+
+    def smtp_QUIT(self, arg):
+        # args is ignored
+        self.push('221 Bye')
+        self.close_when_done()
+
+    def _strip_command_keyword(self, keyword, arg):
+        keylen = len(keyword)
+        if arg[:keylen].upper() == keyword:
+            return arg[keylen:].strip()
+        return ''
+
+    def _getaddr(self, arg):
+        if not arg:
+            return '', ''
+        if arg.lstrip().startswith('<'):
+            address, rest = get_angle_addr(arg)
+        else:
+            address, rest = get_addr_spec(arg)
+        if not address:
+            return address, rest
+        return address.addr_spec, rest
+
+    def _getparams(self, params):
+        # Return params as dictionary. Return None if not all parameters
+        # appear to be syntactically valid according to RFC 1869.
+        result = {}
+        for param in params:
+            param, eq, value = param.partition('=')
+            if not param.isalnum() or eq and not value:
+                return None
+            result[param] = value if eq else True
+        return result
+
+    def smtp_HELP(self, arg):
+        if arg:
+            extended = ' [SP <mail-parameters>]'
+            lc_arg = arg.upper()
+            if lc_arg == 'EHLO':
+                self.push('250 Syntax: EHLO hostname')
+            elif lc_arg == 'HELO':
+                self.push('250 Syntax: HELO hostname')
+            elif lc_arg == 'MAIL':
+                msg = '250 Syntax: MAIL FROM: <address>'
+                if self.extended_smtp:
+                    msg += extended
+                self.push(msg)
+            elif lc_arg == 'RCPT':
+                msg = '250 Syntax: RCPT TO: <address>'
+                if self.extended_smtp:
+                    msg += extended
+                self.push(msg)
+            elif lc_arg == 'DATA':
+                self.push('250 Syntax: DATA')
+            elif lc_arg == 'RSET':
+                self.push('250 Syntax: RSET')
+            elif lc_arg == 'NOOP':
+                self.push('250 Syntax: NOOP')
+            elif lc_arg == 'QUIT':
+                self.push('250 Syntax: QUIT')
+            elif lc_arg == 'VRFY':
+                self.push('250 Syntax: VRFY <address>')
+            else:
+                self.push('501 Supported commands: EHLO HELO MAIL RCPT '
+                          'DATA RSET NOOP QUIT VRFY')
+        else:
+            self.push('250 Supported commands: EHLO HELO MAIL RCPT DATA '
+                      'RSET NOOP QUIT VRFY')
+
+    def smtp_VRFY(self, arg):
+        if arg:
+            address, params = self._getaddr(arg)
+            if address:
+                self.push('252 Cannot VRFY user, but will accept message '
+                          'and attempt delivery')
+            else:
+                self.push('502 Could not VRFY %s' % arg)
+        else:
+            self.push('501 Syntax: VRFY <address>')
+
+    def smtp_MAIL(self, arg):
+        if not self.seen_greeting:
+            self.push('503 Error: send HELO first')
+            return
+        print('===> MAIL', arg, file=DEBUGSTREAM)
+        syntaxerr = '501 Syntax: MAIL FROM: <address>'
+        if self.extended_smtp:
+            syntaxerr += ' [SP <mail-parameters>]'
+        if arg is None:
+            self.push(syntaxerr)
+            return
+        arg = self._strip_command_keyword('FROM:', arg)
+        address, params = self._getaddr(arg)
+        if not address:
+            self.push(syntaxerr)
+            return
+        if not self.extended_smtp and params:
+            self.push(syntaxerr)
+            return
+        if self.mailfrom:
+            self.push('503 Error: nested MAIL command')
+            return
+        self.mail_options = params.upper().split()
+        params = self._getparams(self.mail_options)
+        if params is None:
+            self.push(syntaxerr)
+            return
+        if not self._decode_data:
+            body = params.pop('BODY', '7BIT')
+            if body not in ['7BIT', '8BITMIME']:
+                self.push('501 Error: BODY can only be one of 7BIT, 8BITMIME')
+                return
+        if self.enable_SMTPUTF8:
+            smtputf8 = params.pop('SMTPUTF8', False)
+            if smtputf8 is True:
+                self.require_SMTPUTF8 = True
+            elif smtputf8 is not False:
+                self.push('501 Error: SMTPUTF8 takes no arguments')
+                return
+        size = params.pop('SIZE', None)
+        if size:
+            if not size.isdigit():
+                self.push(syntaxerr)
+                return
+            elif self.data_size_limit and int(size) > self.data_size_limit:
+                self.push('552 Error: message size exceeds fixed maximum message size')
+                return
+        if len(params.keys()) > 0:
+            self.push('555 MAIL FROM parameters not recognized or not implemented')
+            return
+        self.mailfrom = address
+        print('sender:', self.mailfrom, file=DEBUGSTREAM)
+        self.push('250 OK')
+
+    def smtp_RCPT(self, arg):
+        if not self.seen_greeting:
+            self.push('503 Error: send HELO first');
+            return
+        print('===> RCPT', arg, file=DEBUGSTREAM)
+        if not self.mailfrom:
+            self.push('503 Error: need MAIL command')
+            return
+        syntaxerr = '501 Syntax: RCPT TO: <address>'
+        if self.extended_smtp:
+            syntaxerr += ' [SP <mail-parameters>]'
+        if arg is None:
+            self.push(syntaxerr)
+            return
+        arg = self._strip_command_keyword('TO:', arg)
+        address, params = self._getaddr(arg)
+        if not address:
+            self.push(syntaxerr)
+            return
+        if not self.extended_smtp and params:
+            self.push(syntaxerr)
+            return
+        self.rcpt_options = params.upper().split()
+        params = self._getparams(self.rcpt_options)
+        if params is None:
+            self.push(syntaxerr)
+            return
+        # XXX currently there are no options we recognize.
+        if len(params.keys()) > 0:
+            self.push('555 RCPT TO parameters not recognized or not implemented')
+            return
+        self.rcpttos.append(address)
+        print('recips:', self.rcpttos, file=DEBUGSTREAM)
+        self.push('250 OK')
+
+    def smtp_RSET(self, arg):
+        if arg:
+            self.push('501 Syntax: RSET')
+            return
+        self._set_rset_state()
+        self.push('250 OK')
+
+    def smtp_DATA(self, arg):
+        if not self.seen_greeting:
+            self.push('503 Error: send HELO first');
+            return
+        if not self.rcpttos:
+            self.push('503 Error: need RCPT command')
+            return
+        if arg:
+            self.push('501 Syntax: DATA')
+            return
+        self.smtp_state = self.DATA
+        self.set_terminator(b'\r\n.\r\n')
+        self.push('354 End data with <CR><LF>.<CR><LF>')
+
+    # Commands that have not been implemented
+    def smtp_EXPN(self, arg):
+        self.push('502 EXPN not implemented')
+
+
+class SMTPServer(asyncore.dispatcher):
+    # SMTPChannel class to use for managing client connections
+    channel_class = SMTPChannel
+
+    def __init__(self, localaddr, remoteaddr,
+                 data_size_limit=DATA_SIZE_DEFAULT, map=None,
+                 enable_SMTPUTF8=False, decode_data=False):
+        self._localaddr = localaddr
+        self._remoteaddr = remoteaddr
+        self.data_size_limit = data_size_limit
+        self.enable_SMTPUTF8 = enable_SMTPUTF8
+        self._decode_data = decode_data
+        if enable_SMTPUTF8 and decode_data:
+            raise ValueError("decode_data and enable_SMTPUTF8 cannot"
+                             " be set to True at the same time")
+        asyncore.dispatcher.__init__(self, map=map)
+        try:
+            gai_results = socket.getaddrinfo(*localaddr,
+                                             type=socket.SOCK_STREAM)
+            self.create_socket(gai_results[0][0], gai_results[0][1])
+            # try to re-use a server port if possible
+            self.set_reuse_addr()
+            self.bind(localaddr)
+            self.listen(5)
+        except:
+            self.close()
+            raise
+        else:
+            print('%s started at %s\n\tLocal addr: %s\n\tRemote addr:%s' % (
+                self.__class__.__name__, time.ctime(time.time()),
+                localaddr, remoteaddr), file=DEBUGSTREAM)
+
+    def handle_accepted(self, conn, addr):
+        print('Incoming connection from %s' % repr(addr), file=DEBUGSTREAM)
+        channel = self.channel_class(self,
+                                     conn,
+                                     addr,
+                                     self.data_size_limit,
+                                     self._map,
+                                     self.enable_SMTPUTF8,
+                                     self._decode_data)
+
+    # API for "doing something useful with the message"
+    def process_message(self, peer, mailfrom, rcpttos, data, **kwargs):
+        """Override this abstract method to handle messages from the client.
+
+        peer is a tuple containing (ipaddr, port) of the client that made the
+        socket connection to our smtp port.
+
+        mailfrom is the raw address the client claims the message is coming
+        from.
+
+        rcpttos is a list of raw addresses the client wishes to deliver the
+        message to.
+
+        data is a string containing the entire full text of the message,
+        headers (if supplied) and all.  It has been `de-transparencied'
+        according to RFC 821, Section 4.5.2.  In other words, a line
+        containing a `.' followed by other text has had the leading dot
+        removed.
+
+        kwargs is a dictionary containing additional information.  It is
+        empty if decode_data=True was given as init parameter, otherwise
+        it will contain the following keys:
+            'mail_options': list of parameters to the mail command.  All
+                            elements are uppercase strings.  Example:
+                            ['BODY=8BITMIME', 'SMTPUTF8'].
+            'rcpt_options': same, for the rcpt command.
+
+        This function should return None for a normal `250 Ok' response;
+        otherwise, it should return the desired response string in RFC 821
+        format.
+
+        """
+        raise NotImplementedError
+
+
+class DebuggingServer(SMTPServer):
+
+    def _print_message_content(self, peer, data):
+        inheaders = 1
+        lines = data.splitlines()
+        for line in lines:
+            # headers first
+            if inheaders and not line:
+                peerheader = 'X-Peer: ' + peer[0]
+                if not isinstance(data, str):
+                    # decoded_data=false; make header match other binary output
+                    peerheader = repr(peerheader.encode('utf-8'))
+                print(peerheader)
+                inheaders = 0
+            if not isinstance(data, str):
+                # Avoid spurious 'str on bytes instance' warning.
+                line = repr(line)
+            print(line)
+
+    def process_message(self, peer, mailfrom, rcpttos, data, **kwargs):
+        print('---------- MESSAGE FOLLOWS ----------')
+        if kwargs:
+            if kwargs.get('mail_options'):
+                print('mail options: %s' % kwargs['mail_options'])
+            if kwargs.get('rcpt_options'):
+                print('rcpt options: %s\n' % kwargs['rcpt_options'])
+        self._print_message_content(peer, data)
+        print('------------ END MESSAGE ------------')
+
+
+class PureProxy(SMTPServer):
+    def __init__(self, *args, **kwargs):
+        if 'enable_SMTPUTF8' in kwargs and kwargs['enable_SMTPUTF8']:
+            raise ValueError("PureProxy does not support SMTPUTF8.")
+        super(PureProxy, self).__init__(*args, **kwargs)
+
+    def process_message(self, peer, mailfrom, rcpttos, data):
+        lines = data.split('\n')
+        # Look for the last header
+        i = 0
+        for line in lines:
+            if not line:
+                break
+            i += 1
+        lines.insert(i, 'X-Peer: %s' % peer[0])
+        data = NEWLINE.join(lines)
+        refused = self._deliver(mailfrom, rcpttos, data)
+        # TBD: what to do with refused addresses?
+        print('we got some refusals:', refused, file=DEBUGSTREAM)
+
+    def _deliver(self, mailfrom, rcpttos, data):
+        import smtplib
+        refused = {}
+        try:
+            s = smtplib.SMTP()
+            s.connect(self._remoteaddr[0], self._remoteaddr[1])
+            try:
+                refused = s.sendmail(mailfrom, rcpttos, data)
+            finally:
+                s.quit()
+        except smtplib.SMTPRecipientsRefused as e:
+            print('got SMTPRecipientsRefused', file=DEBUGSTREAM)
+            refused = e.recipients
+        except (OSError, smtplib.SMTPException) as e:
+            print('got', e.__class__, file=DEBUGSTREAM)
+            # All recipients were refused.  If the exception had an associated
+            # error code, use it.  Otherwise,fake it with a non-triggering
+            # exception code.
+            errcode = getattr(e, 'smtp_code', -1)
+            errmsg = getattr(e, 'smtp_error', 'ignore')
+            for r in rcpttos:
+                refused[r] = (errcode, errmsg)
+        return refused
+
+
+class Options:
+    setuid = True
+    classname = 'PureProxy'
+    size_limit = None
+    enable_SMTPUTF8 = False
+
+
+def parseargs():
+    global DEBUGSTREAM
+    try:
+        opts, args = getopt.getopt(
+            sys.argv[1:], 'nVhc:s:du',
+            ['class=', 'nosetuid', 'version', 'help', 'size=', 'debug',
+             'smtputf8'])
+    except getopt.error as e:
+        usage(1, e)
+
+    options = Options()
+    for opt, arg in opts:
+        if opt in ('-h', '--help'):
+            usage(0)
+        elif opt in ('-V', '--version'):
+            print(__version__)
+            sys.exit(0)
+        elif opt in ('-n', '--nosetuid'):
+            options.setuid = False
+        elif opt in ('-c', '--class'):
+            options.classname = arg
+        elif opt in ('-d', '--debug'):
+            DEBUGSTREAM = sys.stderr
+        elif opt in ('-u', '--smtputf8'):
+            options.enable_SMTPUTF8 = True
+        elif opt in ('-s', '--size'):
+            try:
+                int_size = int(arg)
+                options.size_limit = int_size
+            except:
+                print('Invalid size: ' + arg, file=sys.stderr)
+                sys.exit(1)
+
+    # parse the rest of the arguments
+    if len(args) < 1:
+        localspec = 'localhost:8025'
+        remotespec = 'localhost:25'
+    elif len(args) < 2:
+        localspec = args[0]
+        remotespec = 'localhost:25'
+    elif len(args) < 3:
+        localspec = args[0]
+        remotespec = args[1]
+    else:
+        usage(1, 'Invalid arguments: %s' % COMMASPACE.join(args))
+
+    # split into host/port pairs
+    i = localspec.find(':')
+    if i < 0:
+        usage(1, 'Bad local spec: %s' % localspec)
+    options.localhost = localspec[:i]
+    try:
+        options.localport = int(localspec[i+1:])
+    except ValueError:
+        usage(1, 'Bad local port: %s' % localspec)
+    i = remotespec.find(':')
+    if i < 0:
+        usage(1, 'Bad remote spec: %s' % remotespec)
+    options.remotehost = remotespec[:i]
+    try:
+        options.remoteport = int(remotespec[i+1:])
+    except ValueError:
+        usage(1, 'Bad remote port: %s' % remotespec)
+    return options
+
+
+if __name__ == '__main__':
+    options = parseargs()
+    # Become nobody
+    classname = options.classname
+    if "." in classname:
+        lastdot = classname.rfind(".")
+        mod = __import__(classname[:lastdot], globals(), locals(), [""])
+        classname = classname[lastdot+1:]
+    else:
+        import __main__ as mod
+    class_ = getattr(mod, classname)
+    proxy = class_((options.localhost, options.localport),
+                   (options.remotehost, options.remoteport),
+                   options.size_limit, enable_SMTPUTF8=options.enable_SMTPUTF8)
+    if options.setuid:
+        try:
+            import pwd
+        except ImportError:
+            print('Cannot import module "pwd"; try running with -n option.', file=sys.stderr)
+            sys.exit(1)
+        nobody = pwd.getpwnam('nobody')[2]
+        try:
+            os.setuid(nobody)
+        except PermissionError:
+            print('Cannot setuid "nobody"; try running with -n option.', file=sys.stderr)
+            sys.exit(1)
+    try:
+        asyncore.loop()
+    except KeyboardInterrupt:
+        pass
diff --git a/Lib/test/test__colorize.py b/Lib/test/test__colorize.py
new file mode 100644
index 0000000000..056a5306ce
--- /dev/null
+++ b/Lib/test/test__colorize.py
@@ -0,0 +1,135 @@
+import contextlib
+import io
+import sys
+import unittest
+import unittest.mock
+import _colorize
+from test.support.os_helper import EnvironmentVarGuard
+
+
+@contextlib.contextmanager
+def clear_env():
+    with EnvironmentVarGuard() as mock_env:
+        for var in "FORCE_COLOR", "NO_COLOR", "PYTHON_COLORS":
+            mock_env.unset(var)
+        yield mock_env
+
+
+def supports_virtual_terminal():
+    if sys.platform == "win32":
+        return unittest.mock.patch("nt._supports_virtual_terminal", return_value=True)
+    else:
+        return contextlib.nullcontext()
+
+
+class TestColorizeFunction(unittest.TestCase):
+    def test_colorized_detection_checks_for_environment_variables(self):
+        def check(env, fallback, expected):
+            with (self.subTest(env=env, fallback=fallback),
+                  clear_env() as mock_env):
+                mock_env.update(env)
+                isatty_mock.return_value = fallback
+                stdout_mock.isatty.return_value = fallback
+                self.assertEqual(_colorize.can_colorize(), expected)
+
+        with (unittest.mock.patch("os.isatty") as isatty_mock,
+              unittest.mock.patch("sys.stdout") as stdout_mock,
+              supports_virtual_terminal()):
+            stdout_mock.fileno.return_value = 1
+
+            for fallback in False, True:
+                check({}, fallback, fallback)
+                check({'TERM': 'dumb'}, fallback, False)
+                check({'TERM': 'xterm'}, fallback, fallback)
+                check({'TERM': ''}, fallback, fallback)
+                check({'FORCE_COLOR': '1'}, fallback, True)
+                check({'FORCE_COLOR': '0'}, fallback, True)
+                check({'FORCE_COLOR': ''}, fallback, fallback)
+                check({'NO_COLOR': '1'}, fallback, False)
+                check({'NO_COLOR': '0'}, fallback, False)
+                check({'NO_COLOR': ''}, fallback, fallback)
+
+            check({'TERM': 'dumb', 'FORCE_COLOR': '1'}, False, True)
+            check({'FORCE_COLOR': '1', 'NO_COLOR': '1'}, True, False)
+
+            for ignore_environment in False, True:
+                # Simulate running with or without `-E`.
+                flags = unittest.mock.MagicMock(ignore_environment=ignore_environment)
+                with unittest.mock.patch("sys.flags", flags):
+                    check({'PYTHON_COLORS': '1'}, True, True)
+                    check({'PYTHON_COLORS': '1'}, False, not ignore_environment)
+                    check({'PYTHON_COLORS': '0'}, True, ignore_environment)
+                    check({'PYTHON_COLORS': '0'}, False, False)
+                    for fallback in False, True:
+                        check({'PYTHON_COLORS': 'x'}, fallback, fallback)
+                        check({'PYTHON_COLORS': ''}, fallback, fallback)
+
+                    check({'TERM': 'dumb', 'PYTHON_COLORS': '1'}, False, not ignore_environment)
+                    check({'NO_COLOR': '1', 'PYTHON_COLORS': '1'}, False, not ignore_environment)
+                    check({'FORCE_COLOR': '1', 'PYTHON_COLORS': '0'}, True, ignore_environment)
+
+    @unittest.skipUnless(sys.platform == "win32", "requires Windows")
+    def test_colorized_detection_checks_on_windows(self):
+        with (clear_env(),
+              unittest.mock.patch("os.isatty") as isatty_mock,
+              unittest.mock.patch("sys.stdout") as stdout_mock,
+              supports_virtual_terminal() as vt_mock):
+            stdout_mock.fileno.return_value = 1
+            isatty_mock.return_value = True
+            stdout_mock.isatty.return_value = True
+
+            vt_mock.return_value = True
+            self.assertEqual(_colorize.can_colorize(), True)
+            vt_mock.return_value = False
+            self.assertEqual(_colorize.can_colorize(), False)
+            import nt
+            del nt._supports_virtual_terminal
+            self.assertEqual(_colorize.can_colorize(), False)
+
+    def test_colorized_detection_checks_for_std_streams(self):
+        with (clear_env(),
+              unittest.mock.patch("os.isatty") as isatty_mock,
+              unittest.mock.patch("sys.stdout") as stdout_mock,
+              unittest.mock.patch("sys.stderr") as stderr_mock,
+              supports_virtual_terminal()):
+            stdout_mock.fileno.return_value = 1
+            stderr_mock.fileno.side_effect = ZeroDivisionError
+            stderr_mock.isatty.side_effect = ZeroDivisionError
+
+            isatty_mock.return_value = True
+            stdout_mock.isatty.return_value = True
+            self.assertEqual(_colorize.can_colorize(), True)
+
+            isatty_mock.return_value = False
+            stdout_mock.isatty.return_value = False
+            self.assertEqual(_colorize.can_colorize(), False)
+
+    def test_colorized_detection_checks_for_file(self):
+        with clear_env(), supports_virtual_terminal():
+
+            with unittest.mock.patch("os.isatty") as isatty_mock:
+                file = unittest.mock.MagicMock()
+                file.fileno.return_value = 1
+                isatty_mock.return_value = True
+                self.assertEqual(_colorize.can_colorize(file=file), True)
+                isatty_mock.return_value = False
+                self.assertEqual(_colorize.can_colorize(file=file), False)
+
+            # No file.fileno.
+            with unittest.mock.patch("os.isatty", side_effect=ZeroDivisionError):
+                file = unittest.mock.MagicMock(spec=['isatty'])
+                file.isatty.return_value = True
+                self.assertEqual(_colorize.can_colorize(file=file), False)
+
+            # file.fileno() raises io.UnsupportedOperation.
+            with unittest.mock.patch("os.isatty", side_effect=ZeroDivisionError):
+                file = unittest.mock.MagicMock()
+                file.fileno.side_effect = io.UnsupportedOperation
+                file.isatty.return_value = True
+                self.assertEqual(_colorize.can_colorize(file=file), True)
+                file.isatty.return_value = False
+                self.assertEqual(_colorize.can_colorize(file=file), False)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/Lib/test/test_charmapcodec.py b/Lib/test/test_charmapcodec.py
index e69f1c6e4b..8ea75d9129 100644
--- a/Lib/test/test_charmapcodec.py
+++ b/Lib/test/test_charmapcodec.py
@@ -26,7 +26,6 @@ def codec_search_function(encoding):
 codecname = 'testcodec'
 
 class CharmapCodecTest(unittest.TestCase):
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_constructorx(self):
         self.assertEqual(str(b'abc', codecname), 'abc')
         self.assertEqual(str(b'xdef', codecname), 'abcdef')
@@ -43,14 +42,12 @@ def test_encodex(self):
         self.assertEqual('dxf'.encode(codecname), b'dabcf')
         self.assertEqual('dxfx'.encode(codecname), b'dabcfabc')
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_constructory(self):
         self.assertEqual(str(b'ydef', codecname), 'def')
         self.assertEqual(str(b'defy', codecname), 'def')
         self.assertEqual(str(b'dyf', codecname), 'df')
         self.assertEqual(str(b'dyfy', codecname), 'df')
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_maptoundefined(self):
         self.assertRaises(UnicodeError, str, b'abc\001', codecname)
 
diff --git a/Lib/test/test_codecs.py b/Lib/test/test_codecs.py
index 085b800b6d..f29e91e088 100644
--- a/Lib/test/test_codecs.py
+++ b/Lib/test/test_codecs.py
@@ -1827,7 +1827,6 @@ def test_decode(self):
         self.assertEqual(codecs.decode(b'[\xff]', 'ascii', errors='ignore'),
                          '[]')
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_encode(self):
         self.assertEqual(codecs.encode('\xe4\xf6\xfc', 'latin-1'),
                          b'\xe4\xf6\xfc')
@@ -1846,7 +1845,6 @@ def test_register(self):
         self.assertRaises(TypeError, codecs.register)
         self.assertRaises(TypeError, codecs.register, 42)
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON; AttributeError: module '_winapi' has no attribute 'GetACP'")
     def test_unregister(self):
         name = "nonexistent_codec_name"
         search_function = mock.Mock()
@@ -1859,28 +1857,23 @@ def test_unregister(self):
         self.assertRaises(LookupError, codecs.lookup, name)
         search_function.assert_not_called()
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_lookup(self):
         self.assertRaises(TypeError, codecs.lookup)
         self.assertRaises(LookupError, codecs.lookup, "__spam__")
         self.assertRaises(LookupError, codecs.lookup, " ")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_getencoder(self):
         self.assertRaises(TypeError, codecs.getencoder)
         self.assertRaises(LookupError, codecs.getencoder, "__spam__")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_getdecoder(self):
         self.assertRaises(TypeError, codecs.getdecoder)
         self.assertRaises(LookupError, codecs.getdecoder, "__spam__")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_getreader(self):
         self.assertRaises(TypeError, codecs.getreader)
         self.assertRaises(LookupError, codecs.getreader, "__spam__")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_getwriter(self):
         self.assertRaises(TypeError, codecs.getwriter)
         self.assertRaises(LookupError, codecs.getwriter, "__spam__")
@@ -1939,7 +1932,6 @@ def test_undefined(self):
             self.assertRaises(UnicodeError,
                 codecs.decode, b'abc', 'undefined', errors)
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_file_closes_if_lookup_error_raised(self):
         mock_open = mock.mock_open()
         with mock.patch('builtins.open', mock_open) as file:
@@ -3287,7 +3279,6 @@ def test_multiple_args(self):
         self.check_note(RuntimeError('a', 'b', 'c'), msg_re)
 
     # http://bugs.python.org/issue19609
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_codec_lookup_failure(self):
         msg = "^unknown encoding: {}$".format(self.codec_name)
         with self.assertRaisesRegex(LookupError, msg):
@@ -3523,8 +3514,6 @@ def test_incremental(self):
                                           False)
         self.assertEqual(decoded, ('abc', 3))
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_mbcs_alias(self):
         # Check that looking up our 'default' codepage will return
         # mbcs when we don't have a more specific one available
diff --git a/Lib/test/test_enum.py b/Lib/test/test_enum.py
index 3989b7d674..bff85a7ec2 100644
--- a/Lib/test/test_enum.py
+++ b/Lib/test/test_enum.py
@@ -1369,10 +1369,12 @@ class Inner(Enum):
             [Outer.a, Outer.b, Outer.Inner],
             )
 
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
     @unittest.skipIf(
-            python_version < (3, 13),
-            'inner classes are still members',
-            )
+        python_version < (3, 13),
+        'inner classes are still members',
+    )
     def test_nested_classes_in_enum_are_not_members(self):
         """Support locally-defined nested classes."""
         class Outer(Enum):
@@ -4555,20 +4557,24 @@ class Color(Enum):
         self.assertEqual(Color.green.value, 3)
         self.assertEqual(Color.yellow.value, 4)
 
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
     @unittest.skipIf(
-            python_version < (3, 13),
-            'mixed types with auto() will raise in 3.13',
-            )
+        python_version < (3, 13),
+        'inner classes are still members',
+    )
     def test_auto_garbage_fail(self):
         with self.assertRaisesRegex(TypeError, 'will require all values to be sortable'):
             class Color(Enum):
                 red = 'red'
                 blue = auto()
 
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
     @unittest.skipIf(
-            python_version < (3, 13),
-            'mixed types with auto() will raise in 3.13',
-            )
+        python_version < (3, 13),
+        'inner classes are still members',
+    )
     def test_auto_garbage_corrected_fail(self):
         with self.assertRaisesRegex(TypeError, 'will require all values to be sortable'):
             class Color(Enum):
@@ -4598,9 +4604,9 @@ def _generate_next_value_(name, start, count, last):
         self.assertEqual(Color.blue.value, 'blue')
 
     @unittest.skipIf(
-            python_version < (3, 13),
-            'auto() will return highest value + 1 in 3.13',
-            )
+        python_version < (3, 13),
+        'inner classes are still members',
+    )
     def test_auto_with_aliases(self):
         class Color(Enum):
             red = auto()
diff --git a/Lib/test/test_float.py b/Lib/test/test_float.py
index 353c1ea9b7..19c17af596 100644
--- a/Lib/test/test_float.py
+++ b/Lib/test/test_float.py
@@ -133,7 +133,7 @@ def check(s):
             with self.assertRaises(ValueError, msg='float(%r)' % (s,)) as cm:
                 float(s)
             self.assertEqual(str(cm.exception),
-                'could not convert string to float: %r' % (s,))
+                             'could not convert string to float: %r' % (s,))
 
         check('\xbd')
         check('123\xbd')
@@ -155,7 +155,9 @@ def check(s):
         # non-UTF-8 byte string
         check(b'123\xa0')
 
-    @support.run_with_locale('LC_NUMERIC', 'fr_FR', 'de_DE')
+    # TODO: RUSTPYTHON
+    @unittest.skip("RustPython panics on this")
+    @support.run_with_locale('LC_NUMERIC', 'fr_FR', 'de_DE', '')
     def test_float_with_comma(self):
         # set locale to something that doesn't use '.' for the decimal point
         # float must not accept the locale specific decimal point but
@@ -290,11 +292,11 @@ def test_is_integer(self):
 
     def test_floatasratio(self):
         for f, ratio in [
-                (0.875, (7, 8)),
-                (-0.875, (-7, 8)),
-                (0.0, (0, 1)),
-                (11.5, (23, 2)),
-            ]:
+            (0.875, (7, 8)),
+            (-0.875, (-7, 8)),
+            (0.0, (0, 1)),
+            (11.5, (23, 2)),
+        ]:
             self.assertEqual(f.as_integer_ratio(), ratio)
 
         for i in range(10000):
@@ -337,7 +339,7 @@ def test_float_containment(self):
             self.assertTrue((f,) == (f,), "(%r,) != (%r,)" % (f, f))
             self.assertTrue({f} == {f}, "{%r} != {%r}" % (f, f))
             self.assertTrue({f : None} == {f: None}, "{%r : None} != "
-                                                   "{%r : None}" % (f, f))
+                                                     "{%r : None}" % (f, f))
 
             # identical containers
             l, t, s, d = [f], (f,), {f}, {f: None}
@@ -667,8 +669,6 @@ def test_float_specials_do_unpack(self):
                           ('<f', LE_FLOAT_NAN)]:
             struct.unpack(fmt, data)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     @support.requires_IEEE_754
     @unittest.skipIf(_testcapi is None, 'needs _testcapi')
     def test_serialized_float_rounding(self):
@@ -776,7 +776,7 @@ def test_issue35560(self):
 class ReprTestCase(unittest.TestCase):
     def test_repr(self):
         with open(os.path.join(os.path.split(__file__)[0],
-                  'floating_points.txt'), encoding="utf-8") as floats_file:
+                               'floating_points.txt'), encoding="utf-8") as floats_file:
             for line in floats_file:
                 line = line.strip()
                 if not line or line.startswith('#'):
@@ -826,7 +826,7 @@ def test_short_repr(self):
             '2.86438000439698e+28',
             '8.89142905246179e+28',
             '3.08578087079232e+35',
-            ]
+        ]
 
         for s in test_strings:
             negs = '-'+s
@@ -883,7 +883,7 @@ def test_overflow(self):
     def test_previous_round_bugs(self):
         # particular cases that have occurred in bug reports
         self.assertEqual(round(562949953421312.5, 1),
-                          562949953421312.5)
+                         562949953421312.5)
         self.assertEqual(round(56294995342131.5, 3),
                          56294995342131.5)
         # round-half-even
@@ -1133,7 +1133,7 @@ def test_invalid_inputs(self):
             '0x1.\uff10p0',
             '0x1p0 \n 0x2p0',
             '0x1p0\0 0x1p0',  # embedded null byte is not end of string
-            ]
+        ]
         for x in invalid_inputs:
             try:
                 result = fromHex(x)
@@ -1152,7 +1152,7 @@ def test_whitespace(self):
             ('1.0', 1.0),
             ('-0x.2', -0.125),
             ('-0.0', -0.0)
-            ]
+        ]
         whitespace = [
             '',
             ' ',
@@ -1162,7 +1162,7 @@ def test_whitespace(self):
             '\f',
             '\v',
             '\r'
-            ]
+        ]
         for inp, expected in value_pairs:
             for lead in whitespace:
                 for trail in whitespace:
diff --git a/Lib/test/test_gzip.py b/Lib/test/test_gzip.py
index 6a709d3f66..42bb7d6984 100644
--- a/Lib/test/test_gzip.py
+++ b/Lib/test/test_gzip.py
@@ -5,7 +5,6 @@
 import functools
 import io
 import os
-import pathlib
 import struct
 import sys
 import unittest
@@ -16,6 +15,7 @@
 from test.support.script_helper import assert_python_ok, assert_python_failure
 
 gzip = import_helper.import_module('gzip')
+zlib = import_helper.import_module('zlib')
 
 data1 = b"""  int length=DEFAULTALLOC, err = Z_OK;
   PyObject *RetVal;
@@ -78,16 +78,18 @@ def test_write(self):
         f.close()
 
     def test_write_read_with_pathlike_file(self):
-        filename = pathlib.Path(self.filename)
+        filename = os_helper.FakePath(self.filename)
         with gzip.GzipFile(filename, 'w') as f:
             f.write(data1 * 50)
         self.assertIsInstance(f.name, str)
+        self.assertEqual(f.name, self.filename)
         with gzip.GzipFile(filename, 'a') as f:
             f.write(data1)
         with gzip.GzipFile(filename) as f:
             d = f.read()
         self.assertEqual(d, data1 * 51)
         self.assertIsInstance(f.name, str)
+        self.assertEqual(f.name, self.filename)
 
     # The following test_write_xy methods test that write accepts
     # the corresponding bytes-like object type as input
@@ -471,15 +473,122 @@ def test_textio_readlines(self):
             with io.TextIOWrapper(f, encoding="ascii") as t:
                 self.assertEqual(t.readlines(), lines)
 
+    def test_fileobj_with_name(self):
+        with open(self.filename, "xb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="x") as f:
+                f.write(b'one')
+                self.assertEqual(f.name, raw.name)
+                self.assertEqual(f.fileno(), raw.fileno())
+                self.assertEqual(f.mode, gzip.WRITE)
+                self.assertIs(f.readable(), False)
+                self.assertIs(f.writable(), True)
+                self.assertIs(f.seekable(), True)
+                self.assertIs(f.closed, False)
+            self.assertIs(f.closed, True)
+            self.assertEqual(f.name, raw.name)
+            self.assertRaises(AttributeError, f.fileno)
+            self.assertEqual(f.mode, gzip.WRITE)
+            self.assertIs(f.readable(), False)
+            self.assertIs(f.writable(), True)
+            self.assertIs(f.seekable(), True)
+
+        with open(self.filename, "wb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="w") as f:
+                f.write(b'two')
+                self.assertEqual(f.name, raw.name)
+                self.assertEqual(f.fileno(), raw.fileno())
+                self.assertEqual(f.mode, gzip.WRITE)
+                self.assertIs(f.readable(), False)
+                self.assertIs(f.writable(), True)
+                self.assertIs(f.seekable(), True)
+                self.assertIs(f.closed, False)
+            self.assertIs(f.closed, True)
+            self.assertEqual(f.name, raw.name)
+            self.assertRaises(AttributeError, f.fileno)
+            self.assertEqual(f.mode, gzip.WRITE)
+            self.assertIs(f.readable(), False)
+            self.assertIs(f.writable(), True)
+            self.assertIs(f.seekable(), True)
+
+        with open(self.filename, "ab") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="a") as f:
+                f.write(b'three')
+                self.assertEqual(f.name, raw.name)
+                self.assertEqual(f.fileno(), raw.fileno())
+                self.assertEqual(f.mode, gzip.WRITE)
+                self.assertIs(f.readable(), False)
+                self.assertIs(f.writable(), True)
+                self.assertIs(f.seekable(), True)
+                self.assertIs(f.closed, False)
+            self.assertIs(f.closed, True)
+            self.assertEqual(f.name, raw.name)
+            self.assertRaises(AttributeError, f.fileno)
+            self.assertEqual(f.mode, gzip.WRITE)
+            self.assertIs(f.readable(), False)
+            self.assertIs(f.writable(), True)
+            self.assertIs(f.seekable(), True)
+
+        with open(self.filename, "rb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="r") as f:
+                self.assertEqual(f.read(), b'twothree')
+                self.assertEqual(f.name, raw.name)
+                self.assertEqual(f.fileno(), raw.fileno())
+                self.assertEqual(f.mode, gzip.READ)
+                self.assertIs(f.readable(), True)
+                self.assertIs(f.writable(), False)
+                self.assertIs(f.seekable(), True)
+                self.assertIs(f.closed, False)
+            self.assertIs(f.closed, True)
+            self.assertEqual(f.name, raw.name)
+            self.assertRaises(AttributeError, f.fileno)
+            self.assertEqual(f.mode, gzip.READ)
+            self.assertIs(f.readable(), True)
+            self.assertIs(f.writable(), False)
+            self.assertIs(f.seekable(), True)
+
     def test_fileobj_from_fdopen(self):
         # Issue #13781: Opening a GzipFile for writing fails when using a
         # fileobj created with os.fdopen().
-        fd = os.open(self.filename, os.O_WRONLY | os.O_CREAT)
-        with os.fdopen(fd, "wb") as f:
-            with gzip.GzipFile(fileobj=f, mode="w") as g:
-                pass
+        fd = os.open(self.filename, os.O_WRONLY | os.O_CREAT | os.O_EXCL)
+        with os.fdopen(fd, "xb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="x") as f:
+                f.write(b'one')
+                self.assertEqual(f.name, '')
+                self.assertEqual(f.fileno(), raw.fileno())
+            self.assertIs(f.closed, True)
+            self.assertEqual(f.name, '')
+            self.assertRaises(AttributeError, f.fileno)
+
+        fd = os.open(self.filename, os.O_WRONLY | os.O_CREAT | os.O_TRUNC)
+        with os.fdopen(fd, "wb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="w") as f:
+                f.write(b'two')
+                self.assertEqual(f.name, '')
+                self.assertEqual(f.fileno(), raw.fileno())
+            self.assertEqual(f.name, '')
+            self.assertRaises(AttributeError, f.fileno)
+
+        fd = os.open(self.filename, os.O_WRONLY | os.O_CREAT | os.O_APPEND)
+        with os.fdopen(fd, "ab") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="a") as f:
+                f.write(b'three')
+                self.assertEqual(f.name, '')
+                self.assertEqual(f.fileno(), raw.fileno())
+            self.assertEqual(f.name, '')
+            self.assertRaises(AttributeError, f.fileno)
+
+        fd = os.open(self.filename, os.O_RDONLY)
+        with os.fdopen(fd, "rb") as raw:
+            with gzip.GzipFile(fileobj=raw, mode="r") as f:
+                self.assertEqual(f.read(), b'twothree')
+                self.assertEqual(f.name, '')
+                self.assertEqual(f.fileno(), raw.fileno())
+            self.assertEqual(f.name, '')
+            self.assertRaises(AttributeError, f.fileno)
 
     def test_fileobj_mode(self):
+        self.assertEqual(gzip.READ, 'rb')
+        self.assertEqual(gzip.WRITE, 'wb')
         gzip.GzipFile(self.filename, "wb").close()
         with open(self.filename, "r+b") as f:
             with gzip.GzipFile(fileobj=f, mode='r') as g:
@@ -507,17 +616,69 @@ def test_fileobj_mode(self):
 
     def test_bytes_filename(self):
         str_filename = self.filename
-        try:
-            bytes_filename = str_filename.encode("ascii")
-        except UnicodeEncodeError:
-            self.skipTest("Temporary file name needs to be ASCII")
+        bytes_filename = os.fsencode(str_filename)
         with gzip.GzipFile(bytes_filename, "wb") as f:
             f.write(data1 * 50)
+        self.assertEqual(f.name, bytes_filename)
         with gzip.GzipFile(bytes_filename, "rb") as f:
             self.assertEqual(f.read(), data1 * 50)
+        self.assertEqual(f.name, bytes_filename)
         # Sanity check that we are actually operating on the right file.
         with gzip.GzipFile(str_filename, "rb") as f:
             self.assertEqual(f.read(), data1 * 50)
+        self.assertEqual(f.name, str_filename)
+
+    def test_fileobj_without_name(self):
+        bio = io.BytesIO()
+        with gzip.GzipFile(fileobj=bio, mode='wb') as f:
+            f.write(data1 * 50)
+            self.assertEqual(f.name, '')
+            self.assertRaises(io.UnsupportedOperation, f.fileno)
+            self.assertEqual(f.mode, gzip.WRITE)
+            self.assertIs(f.readable(), False)
+            self.assertIs(f.writable(), True)
+            self.assertIs(f.seekable(), True)
+            self.assertIs(f.closed, False)
+        self.assertIs(f.closed, True)
+        self.assertEqual(f.name, '')
+        self.assertRaises(AttributeError, f.fileno)
+        self.assertEqual(f.mode, gzip.WRITE)
+        self.assertIs(f.readable(), False)
+        self.assertIs(f.writable(), True)
+        self.assertIs(f.seekable(), True)
+
+        bio.seek(0)
+        with gzip.GzipFile(fileobj=bio, mode='rb') as f:
+            self.assertEqual(f.read(), data1 * 50)
+            self.assertEqual(f.name, '')
+            self.assertRaises(io.UnsupportedOperation, f.fileno)
+            self.assertEqual(f.mode, gzip.READ)
+            self.assertIs(f.readable(), True)
+            self.assertIs(f.writable(), False)
+            self.assertIs(f.seekable(), True)
+            self.assertIs(f.closed, False)
+        self.assertIs(f.closed, True)
+        self.assertEqual(f.name, '')
+        self.assertRaises(AttributeError, f.fileno)
+        self.assertEqual(f.mode, gzip.READ)
+        self.assertIs(f.readable(), True)
+        self.assertIs(f.writable(), False)
+        self.assertIs(f.seekable(), True)
+
+    def test_fileobj_and_filename(self):
+        filename2 = self.filename + 'new'
+        with (open(self.filename, 'wb') as fileobj,
+              gzip.GzipFile(fileobj=fileobj, filename=filename2, mode='wb') as f):
+            f.write(data1 * 50)
+            self.assertEqual(f.name, filename2)
+        with (open(self.filename, 'rb') as fileobj,
+              gzip.GzipFile(fileobj=fileobj, filename=filename2, mode='rb') as f):
+            self.assertEqual(f.read(), data1 * 50)
+            self.assertEqual(f.name, filename2)
+        # Sanity check that we are actually operating on the right file.
+        with gzip.GzipFile(self.filename, 'rb') as f:
+            self.assertEqual(f.read(), data1 * 50)
+            self.assertEqual(f.name, self.filename)
 
     def test_decompress_limited(self):
         """Decompressed data buffering should be limited"""
@@ -552,8 +713,18 @@ def test_compress_mtime(self):
                         f.read(1) # to set mtime attribute
                         self.assertEqual(f.mtime, mtime)
 
+    def test_compress_mtime_default(self):
+        # test for gh-125260
+        datac = gzip.compress(data1, mtime=0)
+        datac2 = gzip.compress(data1)
+        self.assertEqual(datac, datac2)
+        datac3 = gzip.compress(data1, mtime=None)
+        self.assertNotEqual(datac, datac3)
+        with gzip.GzipFile(fileobj=io.BytesIO(datac3), mode="rb") as f:
+            f.read(1) # to set mtime attribute
+            self.assertGreater(f.mtime, 1)
+
     def test_compress_correct_level(self):
-        # gzip.compress calls with mtime == 0 take a different code path.
         for mtime in (0, 42):
             with self.subTest(mtime=mtime):
                 nocompress = gzip.compress(data1, compresslevel=0, mtime=mtime)
@@ -561,6 +732,17 @@ def test_compress_correct_level(self):
                 self.assertIn(data1, nocompress)
                 self.assertNotIn(data1, yescompress)
 
+    def test_issue112346(self):
+        # The OS byte should be 255, this should not change between Python versions.
+        for mtime in (0, 42):
+            with self.subTest(mtime=mtime):
+                compress = gzip.compress(data1, compresslevel=1, mtime=mtime)
+                self.assertEqual(
+                    struct.unpack("<IxB", compress[4:10]),
+                    (mtime, 255),
+                    "Gzip header does not properly set either mtime or OS byte."
+                )
+
     def test_decompress(self):
         for data in (data1, data2):
             buf = io.BytesIO()
@@ -616,6 +798,66 @@ def test_issue44439(self):
             self.assertEqual(f.write(q), LENGTH)
             self.assertEqual(f.tell(), LENGTH)
 
+    def test_flush_flushes_compressor(self):
+        # See issue GH-105808.
+        b = io.BytesIO()
+        message = b"important message here."
+        with gzip.GzipFile(fileobj=b, mode='w') as f:
+            f.write(message)
+            f.flush()
+            partial_data = b.getvalue()
+        full_data = b.getvalue()
+        self.assertEqual(gzip.decompress(full_data), message)
+        # The partial data should contain the gzip header and the complete
+        # message, but not the end-of-stream markers (so we can't just
+        # decompress it directly).
+        with self.assertRaises(EOFError):
+            gzip.decompress(partial_data)
+        d = zlib.decompressobj(wbits=-zlib.MAX_WBITS)
+        f = io.BytesIO(partial_data)
+        gzip._read_gzip_header(f)
+        read_message = d.decompress(f.read())
+        self.assertEqual(read_message, message)
+
+    def test_flush_modes(self):
+        # Make sure the argument to flush is properly passed to the
+        # zlib.compressobj; see issue GH-105808.
+        class FakeCompressor:
+            def __init__(self):
+                self.modes = []
+            def compress(self, data):
+                return b''
+            def flush(self, mode=-1):
+                self.modes.append(mode)
+                return b''
+        b = io.BytesIO()
+        fc = FakeCompressor()
+        with gzip.GzipFile(fileobj=b, mode='w') as f:
+            f.compress = fc
+            f.flush()
+            f.flush(50)
+            f.flush(zlib_mode=100)
+        # The implicit close will also flush the compressor.
+        expected_modes = [
+            zlib.Z_SYNC_FLUSH,
+            50,
+            100,
+            -1,
+        ]
+        self.assertEqual(fc.modes, expected_modes)
+
+    def test_write_seek_write(self):
+        # Make sure that offset is up-to-date before seeking
+        # See issue GH-108111
+        b = io.BytesIO()
+        message = b"important message here."
+        with gzip.GzipFile(fileobj=b, mode='w') as f:
+            f.write(message)
+            f.seek(len(message))
+            f.write(message)
+        data = b.getvalue()
+        self.assertEqual(gzip.decompress(data), message * 2)
+
 
 class TestOpen(BaseTest):
     def test_binary_modes(self):
@@ -646,13 +888,16 @@ def test_binary_modes(self):
             self.assertEqual(file_data, uncompressed)
 
     def test_pathlike_file(self):
-        filename = pathlib.Path(self.filename)
+        filename = os_helper.FakePath(self.filename)
         with gzip.open(filename, "wb") as f:
             f.write(data1 * 50)
+        self.assertEqual(f.name, self.filename)
         with gzip.open(filename, "ab") as f:
             f.write(data1)
+        self.assertEqual(f.name, self.filename)
         with gzip.open(filename) as f:
             self.assertEqual(f.read(), data1 * 51)
+        self.assertEqual(f.name, self.filename)
 
     def test_implicit_binary_modes(self):
         # Test implicit binary modes (no "b" or "t" in mode string).
@@ -682,7 +927,6 @@ def test_implicit_binary_modes(self):
             file_data = gzip.decompress(f.read())
             self.assertEqual(file_data, uncompressed)
 
-    @unittest.skipIf(sys.platform == 'win32', "TODO: RUSTPYTHON, windows text mode")
     def test_text_modes(self):
         uncompressed = data1.decode("ascii") * 50
         uncompressed_raw = uncompressed.replace("\n", os.linesep)
diff --git a/Lib/test/test_importlib/frozen/test_loader.py b/Lib/test/test_importlib/frozen/test_loader.py
index 4f1af454b5..b1eb399d93 100644
--- a/Lib/test/test_importlib/frozen/test_loader.py
+++ b/Lib/test/test_importlib/frozen/test_loader.py
@@ -7,6 +7,7 @@
 import contextlib
 import marshal
 import os.path
+import sys
 import types
 import unittest
 import warnings
@@ -77,6 +78,7 @@ def test_module(self):
         self.assertTrue(hasattr(module, '__spec__'))
         self.assertEqual(module.__spec__.loader_state.origname, name)
 
+    @unittest.skipIf(sys.platform == "win32", "TODO: RUSTPYTHON")
     def test_package(self):
         name = '__phello__'
         module, output = self.exec_module(name)
@@ -90,6 +92,7 @@ def test_package(self):
         self.assertEqual(output, 'Hello world!\n')
         self.assertEqual(module.__spec__.loader_state.origname, name)
 
+    @unittest.skipIf(sys.platform == 'win32', "TODO:RUSTPYTHON Flaky on Windows")
     def test_lacking_parent(self):
         name = '__phello__.spam'
         with util.uncache('__phello__'):
@@ -147,6 +150,7 @@ def test_get_source(self):
             result = self.machinery.FrozenImporter.get_source('__hello__')
         self.assertIsNone(result)
 
+    @unittest.skipIf(sys.platform == "win32", "TODO: RUSTPYTHON")
     def test_is_package(self):
         # Should be able to tell what is a package.
         test_for = (('__hello__', False), ('__phello__', True),
diff --git a/Lib/test/test_importlib/resources/test_files.py b/Lib/test/test_importlib/resources/test_files.py
index 1450cfb310..1d04cda1a8 100644
--- a/Lib/test/test_importlib/resources/test_files.py
+++ b/Lib/test/test_importlib/resources/test_files.py
@@ -52,6 +52,10 @@ class OpenDiskTests(FilesTests, unittest.TestCase):
     def setUp(self):
         self.data = data01
 
+    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
+    def test_read_bytes(self):
+        super().test_read_bytes()
+
 
 class OpenZipTests(FilesTests, util.ZipSetup, unittest.TestCase):
     pass
@@ -63,6 +67,9 @@ def setUp(self):
 
         self.data = namespacedata01
 
+    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
+    def test_read_bytes(self):
+        super().test_read_bytes()
 
 class SiteDir:
     def setUp(self):
diff --git a/Lib/test/test_importlib/source/test_finder.py b/Lib/test/test_importlib/source/test_finder.py
index 17d09d4cee..12db7c7d35 100644
--- a/Lib/test/test_importlib/source/test_finder.py
+++ b/Lib/test/test_importlib/source/test_finder.py
@@ -168,7 +168,6 @@ def test_no_read_directory(self):
         found = self._find(finder, 'doesnotexist')
         self.assertEqual(found, self.NOT_FOUND)
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_ignore_file(self):
         # If a directory got changed to a file from underneath us, then don't
         # worry about looking for submodules.
diff --git a/Lib/test/test_list.py b/Lib/test/test_list.py
index 575a77db0b..c82bf5067d 100644
--- a/Lib/test/test_list.py
+++ b/Lib/test/test_list.py
@@ -22,6 +22,8 @@ def test_basic(self):
 
         if sys.maxsize == 0x7fffffff:
             # This test can currently only work on 32-bit machines.
+            # XXX If/when PySequence_Length() returns a ssize_t, it should be
+            # XXX re-enabled.
             # Verify clearing of bug #556025.
             # This assumes that the max data size (sys.maxint) == max
             # address size this also assumes that the address size is at
@@ -97,7 +99,7 @@ def imul(a, b): a *= b
         self.assertRaises((MemoryError, OverflowError), imul, lst, n)
 
     # TODO: RUSTPYTHON
-    @unittest.expectedFailure
+    @unittest.skip("Crashes on windows debug build")
     def test_list_resize_overflow(self):
         # gh-97616: test new_allocated * sizeof(PyObject*) overflow
         # check in list_resize()
@@ -105,7 +107,7 @@ def test_list_resize_overflow(self):
         del lst[1:]
         self.assertEqual(len(lst), 1)
 
-        size = ((2 ** (tuple.__itemsize__ * 8) - 1) // 2)
+        size = sys.maxsize
         with self.assertRaises((MemoryError, OverflowError)):
             lst * size
         with self.assertRaises((MemoryError, OverflowError)):
@@ -117,7 +119,7 @@ def check(n):
             l = [0] * n
             s = repr(l)
             self.assertEqual(s,
-                '[' + ', '.join(['0'] * n) + ']')
+                             '[' + ', '.join(['0'] * n) + ']')
         check(10)       # check our checking code
         check(1000000)
 
@@ -206,6 +208,7 @@ class L(list): pass
         with self.assertRaises(TypeError):
             (3,) + L([1,2])
 
+    # TODO: RUSTPYTHON
     @unittest.skip("TODO: RUSTPYTHON; hang")
     def test_equal_operator_modifying_operand(self):
         # test fix for seg fault reported in bpo-38588 part 2.
@@ -232,6 +235,33 @@ def __eq__(self, other):
         list4 = [1]
         self.assertFalse(list3 == list4)
 
+    # TODO: RUSTPYTHON
+    @unittest.skip("TODO: RUSTPYTHON; hang")
+    def test_lt_operator_modifying_operand(self):
+        # See gh-120298
+        class evil:
+            def __lt__(self, other):
+                other.clear()
+                return NotImplemented
+
+        a = [[evil()]]
+        with self.assertRaises(TypeError):
+            a[0] < a
+
+    def test_list_index_modifing_operand(self):
+        # See gh-120384
+        class evil:
+            def __init__(self, lst):
+                self.lst = lst
+            def __iter__(self):
+                yield from self.lst
+                self.lst.clear()
+
+        lst = list(range(5))
+        operand = evil(lst)
+        with self.assertRaises(ValueError):
+            lst[::-1] = operand
+
     @cpython_only
     def test_preallocation(self):
         iterable = [0] * 10
diff --git a/Lib/test/test_listcomps.py b/Lib/test/test_listcomps.py
index 91bf2547ed..ad1c5053a3 100644
--- a/Lib/test/test_listcomps.py
+++ b/Lib/test/test_listcomps.py
@@ -1,6 +1,11 @@
 import doctest
+import textwrap
+import traceback
+import types
 import unittest
 
+from test.support import BrokenIter
+
 
 doctests = """
 ########### Tests borrowed from or inspired by test_genexps.py ############
@@ -87,65 +92,661 @@
     >>> [None for i in range(10)]
     [None, None, None, None, None, None, None, None, None, None]
 
-########### Tests for various scoping corner cases ############
-
-Return lambdas that use the iteration variable as a default argument
-
-    >>> items = [(lambda i=i: i) for i in range(5)]
-    >>> [x() for x in items]
-    [0, 1, 2, 3, 4]
-
-Same again, only this time as a closure variable
-
-    >>> items = [(lambda: i) for i in range(5)]
-    >>> [x() for x in items]
-    [4, 4, 4, 4, 4]
-
-Another way to test that the iteration variable is local to the list comp
-
-    >>> items = [(lambda: i) for i in range(5)]
-    >>> i = 20
-    >>> [x() for x in items]
-    [4, 4, 4, 4, 4]
-
-And confirm that a closure can jump over the list comp scope
-
-    >>> items = [(lambda: y) for i in range(5)]
-    >>> y = 2
-    >>> [x() for x in items]
-    [2, 2, 2, 2, 2]
-
-We also repeat each of the above scoping tests inside a function
-
-    >>> def test_func():
-    ...     items = [(lambda i=i: i) for i in range(5)]
-    ...     return [x() for x in items]
-    >>> test_func()
-    [0, 1, 2, 3, 4]
-
-    >>> def test_func():
-    ...     items = [(lambda: i) for i in range(5)]
-    ...     return [x() for x in items]
-    >>> test_func()
-    [4, 4, 4, 4, 4]
-
-    >>> def test_func():
-    ...     items = [(lambda: i) for i in range(5)]
-    ...     i = 20
-    ...     return [x() for x in items]
-    >>> test_func()
-    [4, 4, 4, 4, 4]
-
-    >>> def test_func():
-    ...     items = [(lambda: y) for i in range(5)]
-    ...     y = 2
-    ...     return [x() for x in items]
-    >>> test_func()
-    [2, 2, 2, 2, 2]
-
 """
 
 
+class ListComprehensionTest(unittest.TestCase):
+    def _check_in_scopes(self, code, outputs=None, ns=None, scopes=None, raises=(),
+                         exec_func=exec):
+        code = textwrap.dedent(code)
+        scopes = scopes or ["module", "class", "function"]
+        for scope in scopes:
+            with self.subTest(scope=scope):
+                if scope == "class":
+                    newcode = textwrap.dedent("""
+                        class _C:
+                            {code}
+                    """).format(code=textwrap.indent(code, "    "))
+                    def get_output(moddict, name):
+                        return getattr(moddict["_C"], name)
+                elif scope == "function":
+                    newcode = textwrap.dedent("""
+                        def _f():
+                            {code}
+                            return locals()
+                        _out = _f()
+                    """).format(code=textwrap.indent(code, "    "))
+                    def get_output(moddict, name):
+                        return moddict["_out"][name]
+                else:
+                    newcode = code
+                    def get_output(moddict, name):
+                        return moddict[name]
+                newns = ns.copy() if ns else {}
+                try:
+                    exec_func(newcode, newns)
+                except raises as e:
+                    # We care about e.g. NameError vs UnboundLocalError
+                    self.assertIs(type(e), raises)
+                else:
+                    for k, v in (outputs or {}).items():
+                        self.assertEqual(get_output(newns, k), v, k)
+
+    def test_lambdas_with_iteration_var_as_default(self):
+        code = """
+            items = [(lambda i=i: i) for i in range(5)]
+            y = [x() for x in items]
+        """
+        outputs = {"y": [0, 1, 2, 3, 4]}
+        self._check_in_scopes(code, outputs)
+
+    def test_lambdas_with_free_var(self):
+        code = """
+            items = [(lambda: i) for i in range(5)]
+            y = [x() for x in items]
+        """
+        outputs = {"y": [4, 4, 4, 4, 4]}
+        self._check_in_scopes(code, outputs)
+
+    def test_class_scope_free_var_with_class_cell(self):
+        class C:
+            def method(self):
+                super()
+                return __class__
+            items = [(lambda: i) for i in range(5)]
+            y = [x() for x in items]
+
+        self.assertEqual(C.y, [4, 4, 4, 4, 4])
+        self.assertIs(C().method(), C)
+
+    def test_references_super(self):
+        code = """
+            res = [super for x in [1]]
+        """
+        self._check_in_scopes(code, outputs={"res": [super]})
+
+    def test_references___class__(self):
+        code = """
+            res = [__class__ for x in [1]]
+        """
+        self._check_in_scopes(code, raises=NameError)
+
+    def test_references___class___defined(self):
+        code = """
+            __class__ = 2
+            res = [__class__ for x in [1]]
+        """
+        self._check_in_scopes(
+            code, outputs={"res": [2]}, scopes=["module", "function"])
+        self._check_in_scopes(code, raises=NameError, scopes=["class"])
+
+    def test_references___class___enclosing(self):
+        code = """
+            __class__ = 2
+            class C:
+                res = [__class__ for x in [1]]
+            res = C.res
+        """
+        self._check_in_scopes(code, raises=NameError)
+
+    def test_super_and_class_cell_in_sibling_comps(self):
+        code = """
+            [super for _ in [1]]
+            [__class__ for _ in [1]]
+        """
+        self._check_in_scopes(code, raises=NameError)
+
+    def test_inner_cell_shadows_outer(self):
+        code = """
+            items = [(lambda: i) for i in range(5)]
+            i = 20
+            y = [x() for x in items]
+        """
+        outputs = {"y": [4, 4, 4, 4, 4], "i": 20}
+        self._check_in_scopes(code, outputs)
+
+    def test_inner_cell_shadows_outer_no_store(self):
+        code = """
+            def f(x):
+                return [lambda: x for x in range(x)], x
+            fns, x = f(2)
+            y = [fn() for fn in fns]
+        """
+        outputs = {"y": [1, 1], "x": 2}
+        self._check_in_scopes(code, outputs)
+
+    def test_closure_can_jump_over_comp_scope(self):
+        code = """
+            items = [(lambda: y) for i in range(5)]
+            y = 2
+            z = [x() for x in items]
+        """
+        outputs = {"z": [2, 2, 2, 2, 2]}
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+
+    def test_cell_inner_free_outer(self):
+        code = """
+            def f():
+                return [lambda: x for x in (x, [1])[1]]
+            x = ...
+            y = [fn() for fn in f()]
+        """
+        outputs = {"y": [1]}
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+
+    def test_free_inner_cell_outer(self):
+        code = """
+            g = 2
+            def f():
+                return g
+            y = [g for x in [1]]
+        """
+        outputs = {"y": [2]}
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+        self._check_in_scopes(code, scopes=["class"], raises=NameError)
+
+    def test_inner_cell_shadows_outer_redefined(self):
+        code = """
+            y = 10
+            items = [(lambda: y) for y in range(5)]
+            x = y
+            y = 20
+            out = [z() for z in items]
+        """
+        outputs = {"x": 10, "out": [4, 4, 4, 4, 4]}
+        self._check_in_scopes(code, outputs)
+
+    def test_shadows_outer_cell(self):
+        code = """
+            def inner():
+                return g
+            [g for g in range(5)]
+            x = inner()
+        """
+        outputs = {"x": -1}
+        self._check_in_scopes(code, outputs, ns={"g": -1})
+
+    def test_explicit_global(self):
+        code = """
+            global g
+            x = g
+            g = 2
+            items = [g for g in [1]]
+            y = g
+        """
+        outputs = {"x": 1, "y": 2, "items": [1]}
+        self._check_in_scopes(code, outputs, ns={"g": 1})
+
+    def test_explicit_global_2(self):
+        code = """
+            global g
+            x = g
+            g = 2
+            items = [g for x in [1]]
+            y = g
+        """
+        outputs = {"x": 1, "y": 2, "items": [2]}
+        self._check_in_scopes(code, outputs, ns={"g": 1})
+
+    def test_explicit_global_3(self):
+        code = """
+            global g
+            fns = [lambda: g for g in [2]]
+            items = [fn() for fn in fns]
+        """
+        outputs = {"items": [2]}
+        self._check_in_scopes(code, outputs, ns={"g": 1})
+
+    def test_assignment_expression(self):
+        code = """
+            x = -1
+            items = [(x:=y) for y in range(3)]
+        """
+        outputs = {"x": 2}
+        # assignment expression in comprehension is disallowed in class scope
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+
+    def test_free_var_in_comp_child(self):
+        code = """
+            lst = range(3)
+            funcs = [lambda: x for x in lst]
+            inc = [x + 1 for x in lst]
+            [x for x in inc]
+            x = funcs[0]()
+        """
+        outputs = {"x": 2}
+        self._check_in_scopes(code, outputs)
+
+    def test_shadow_with_free_and_local(self):
+        code = """
+            lst = range(3)
+            x = -1
+            funcs = [lambda: x for x in lst]
+            items = [x + 1 for x in lst]
+        """
+        outputs = {"x": -1}
+        self._check_in_scopes(code, outputs)
+
+    def test_shadow_comp_iterable_name(self):
+        code = """
+            x = [1]
+            y = [x for x in x]
+        """
+        outputs = {"x": [1]}
+        self._check_in_scopes(code, outputs)
+
+    def test_nested_free(self):
+        code = """
+            x = 1
+            def g():
+                [x for x in range(3)]
+                return x
+            g()
+        """
+        outputs = {"x": 1}
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+
+    def test_introspecting_frame_locals(self):
+        code = """
+            import sys
+            [i for i in range(2)]
+            i = 20
+            sys._getframe().f_locals
+        """
+        outputs = {"i": 20}
+        self._check_in_scopes(code, outputs)
+
+    def test_nested(self):
+        code = """
+            l = [2, 3]
+            y = [[x ** 2 for x in range(x)] for x in l]
+        """
+        outputs = {"y": [[0, 1], [0, 1, 4]]}
+        self._check_in_scopes(code, outputs)
+
+    def test_nested_2(self):
+        code = """
+            l = [1, 2, 3]
+            x = 3
+            y = [x for [x ** x for x in range(x)][x - 1] in l]
+        """
+        outputs = {"y": [3, 3, 3]}
+        self._check_in_scopes(code, outputs, scopes=["module", "function"])
+        self._check_in_scopes(code, scopes=["class"], raises=NameError)
+
+    def test_nested_3(self):
+        code = """
+            l = [(1, 2), (3, 4), (5, 6)]
+            y = [x for (x, [x ** x for x in range(x)][x - 1]) in l]
+        """
+        outputs = {"y": [1, 3, 5]}
+        self._check_in_scopes(code, outputs)
+
+    def test_nested_4(self):
+        code = """
+            items = [([lambda: x for x in range(2)], lambda: x) for x in range(3)]
+            out = [([fn() for fn in fns], fn()) for fns, fn in items]
+        """
+        outputs = {"out": [([1, 1], 2), ([1, 1], 2), ([1, 1], 2)]}
+        self._check_in_scopes(code, outputs)
+
+    def test_nameerror(self):
+        code = """
+            [x for x in [1]]
+            x
+        """
+
+        self._check_in_scopes(code, raises=NameError)
+
+    def test_dunder_name(self):
+        code = """
+            y = [__x for __x in [1]]
+        """
+        outputs = {"y": [1]}
+        self._check_in_scopes(code, outputs)
+
+    def test_unbound_local_after_comprehension(self):
+        def f():
+            if False:
+                x = 0
+            [x for x in [1]]
+            return x
+
+        with self.assertRaises(UnboundLocalError):
+            f()
+
+    def test_unbound_local_inside_comprehension(self):
+        def f():
+            l = [None]
+            return [1 for (l[0], l) in [[1, 2]]]
+
+        with self.assertRaises(UnboundLocalError):
+            f()
+
+    def test_global_outside_cellvar_inside_plus_freevar(self):
+        code = """
+            a = 1
+            def f():
+                func, = [(lambda: b) for b in [a]]
+                return b, func()
+            x = f()
+        """
+        self._check_in_scopes(
+            code, {"x": (2, 1)}, ns={"b": 2}, scopes=["function", "module"])
+        # inside a class, the `a = 1` assignment is not visible
+        self._check_in_scopes(code, raises=NameError, scopes=["class"])
+
+    def test_cell_in_nested_comprehension(self):
+        code = """
+            a = 1
+            def f():
+                (func, inner_b), = [[lambda: b for b in c] + [b] for c in [[a]]]
+                return b, inner_b, func()
+            x = f()
+        """
+        self._check_in_scopes(
+            code, {"x": (2, 2, 1)}, ns={"b": 2}, scopes=["function", "module"])
+        # inside a class, the `a = 1` assignment is not visible
+        self._check_in_scopes(code, raises=NameError, scopes=["class"])
+
+    def test_name_error_in_class_scope(self):
+        code = """
+            y = 1
+            [x + y for x in range(2)]
+        """
+        self._check_in_scopes(code, raises=NameError, scopes=["class"])
+
+    def test_global_in_class_scope(self):
+        code = """
+            y = 2
+            vals = [(x, y) for x in range(2)]
+        """
+        outputs = {"vals": [(0, 1), (1, 1)]}
+        self._check_in_scopes(code, outputs, ns={"y": 1}, scopes=["class"])
+
+    def test_in_class_scope_inside_function_1(self):
+        code = """
+            class C:
+                y = 2
+                vals = [(x, y) for x in range(2)]
+            vals = C.vals
+        """
+        outputs = {"vals": [(0, 1), (1, 1)]}
+        self._check_in_scopes(code, outputs, ns={"y": 1}, scopes=["function"])
+
+    def test_in_class_scope_inside_function_2(self):
+        code = """
+            y = 1
+            class C:
+                y = 2
+                vals = [(x, y) for x in range(2)]
+            vals = C.vals
+        """
+        outputs = {"vals": [(0, 1), (1, 1)]}
+        self._check_in_scopes(code, outputs, scopes=["function"])
+
+    def test_in_class_scope_with_global(self):
+        code = """
+            y = 1
+            class C:
+                global y
+                y = 2
+                # Ensure the listcomp uses the global, not the value in the
+                # class namespace
+                locals()['y'] = 3
+                vals = [(x, y) for x in range(2)]
+            vals = C.vals
+        """
+        outputs = {"vals": [(0, 2), (1, 2)]}
+        self._check_in_scopes(code, outputs, scopes=["module", "class"])
+        outputs = {"vals": [(0, 1), (1, 1)]}
+        self._check_in_scopes(code, outputs, scopes=["function"])
+
+    def test_in_class_scope_with_nonlocal(self):
+        code = """
+            y = 1
+            class C:
+                nonlocal y
+                y = 2
+                # Ensure the listcomp uses the global, not the value in the
+                # class namespace
+                locals()['y'] = 3
+                vals = [(x, y) for x in range(2)]
+            vals = C.vals
+        """
+        outputs = {"vals": [(0, 2), (1, 2)]}
+        self._check_in_scopes(code, outputs, scopes=["function"])
+
+    def test_nested_has_free_var(self):
+        code = """
+            items = [a for a in [1] if [a for _ in [0]]]
+        """
+        outputs = {"items": [1]}
+        self._check_in_scopes(code, outputs, scopes=["class"])
+
+    def test_nested_free_var_not_bound_in_outer_comp(self):
+        code = """
+            z = 1
+            items = [a for a in [1] if [x for x in [1] if z]]
+        """
+        self._check_in_scopes(code, {"items": [1]}, scopes=["module", "function"])
+        self._check_in_scopes(code, {"items": []}, ns={"z": 0}, scopes=["class"])
+
+    def test_nested_free_var_in_iter(self):
+        code = """
+            items = [_C for _C in [1] for [0, 1][[x for x in [1] if _C][0]] in [2]]
+        """
+        self._check_in_scopes(code, {"items": [1]})
+
+    def test_nested_free_var_in_expr(self):
+        code = """
+            items = [(_C, [x for x in [1] if _C]) for _C in [0, 1]]
+        """
+        self._check_in_scopes(code, {"items": [(0, []), (1, [1])]})
+
+    def test_nested_listcomp_in_lambda(self):
+        code = """
+            f = [(z, lambda y: [(x, y, z) for x in [3]]) for z in [1]]
+            (z, func), = f
+            out = func(2)
+        """
+        self._check_in_scopes(code, {"z": 1, "out": [(3, 2, 1)]})
+
+    def test_lambda_in_iter(self):
+        code = """
+            (func, c), = [(a, b) for b in [1] for a in [lambda : a]]
+            d = func()
+            assert d is func
+            # must use "a" in this scope
+            e = a if False else None
+        """
+        self._check_in_scopes(code, {"c": 1, "e": None})
+
+    def test_assign_to_comp_iter_var_in_outer_function(self):
+        code = """
+            a = [1 for a in [0]]
+        """
+        self._check_in_scopes(code, {"a": [1]}, scopes=["function"])
+
+    def test_no_leakage_to_locals(self):
+        code = """
+            def b():
+                [a for b in [1] for _ in []]
+                return b, locals()
+            r, s = b()
+            x = r is b
+            y = list(s.keys())
+        """
+        self._check_in_scopes(code, {"x": True, "y": []}, scopes=["module"])
+        self._check_in_scopes(code, {"x": True, "y": ["b"]}, scopes=["function"])
+        self._check_in_scopes(code, raises=NameError, scopes=["class"])
+
+    def test_iter_var_available_in_locals(self):
+        code = """
+            l = [1, 2]
+            y = 0
+            items = [locals()["x"] for x in l]
+            items2 = [vars()["x"] for x in l]
+            items3 = [("x" in dir()) for x in l]
+            items4 = [eval("x") for x in l]
+            # x is available, and does not overwrite y
+            [exec("y = x") for x in l]
+        """
+        self._check_in_scopes(
+            code,
+            {
+                "items": [1, 2],
+                "items2": [1, 2],
+                "items3": [True, True],
+                "items4": [1, 2],
+                "y": 0
+            }
+        )
+
+    def test_comp_in_try_except(self):
+        template = """
+            value = ["ab"]
+            result = snapshot = None
+            try:
+                result = [{func}(value) for value in value]
+            except:
+                snapshot = value
+                raise
+        """
+        # No exception.
+        code = template.format(func='len')
+        self._check_in_scopes(code, {"value": ["ab"], "result": [2], "snapshot": None})
+        # Handles exception.
+        code = template.format(func='int')
+        self._check_in_scopes(code, {"value": ["ab"], "result": None, "snapshot": ["ab"]},
+                              raises=ValueError)
+
+    def test_comp_in_try_finally(self):
+        template = """
+            value = ["ab"]
+            result = snapshot = None
+            try:
+                result = [{func}(value) for value in value]
+            finally:
+                snapshot = value
+        """
+        # No exception.
+        code = template.format(func='len')
+        self._check_in_scopes(code, {"value": ["ab"], "result": [2], "snapshot": ["ab"]})
+        # Handles exception.
+        code = template.format(func='int')
+        self._check_in_scopes(code, {"value": ["ab"], "result": None, "snapshot": ["ab"]},
+                              raises=ValueError)
+
+    def test_exception_in_post_comp_call(self):
+        code = """
+            value = [1, None]
+            try:
+                [v for v in value].sort()
+            except:
+                pass
+        """
+        self._check_in_scopes(code, {"value": [1, None]})
+
+    def test_frame_locals(self):
+        code = """
+            val = [sys._getframe().f_locals for a in [0]][0]["a"]
+        """
+        import sys
+        self._check_in_scopes(code, {"val": 0}, ns={"sys": sys})
+
+    def _recursive_replace(self, maybe_code):
+        if not isinstance(maybe_code, types.CodeType):
+            return maybe_code
+        return maybe_code.replace(co_consts=tuple(
+            self._recursive_replace(c) for c in maybe_code.co_consts
+        ))
+
+    def _replacing_exec(self, code_string, ns):
+        co = compile(code_string, "<string>", "exec")
+        co = self._recursive_replace(co)
+        exec(co, ns)
+
+    def test_code_replace(self):
+        code = """
+            x = 3
+            [x for x in (1, 2)]
+            dir()
+            y = [x]
+        """
+        self._check_in_scopes(code, {"y": [3], "x": 3})
+        self._check_in_scopes(code, {"y": [3], "x": 3}, exec_func=self._replacing_exec)
+
+    def test_code_replace_extended_arg(self):
+        num_names = 300
+        assignments = "; ".join(f"x{i} = {i}" for i in range(num_names))
+        name_list = ", ".join(f"x{i}" for i in range(num_names))
+        expected = {
+            "y": list(range(num_names)),
+            **{f"x{i}": i for i in range(num_names)}
+        }
+        code = f"""
+            {assignments}
+            [({name_list}) for {name_list} in (range(300),)]
+            dir()
+            y = [{name_list}]
+        """
+        self._check_in_scopes(code, expected)
+        self._check_in_scopes(code, expected, exec_func=self._replacing_exec)
+
+    def test_multiple_comprehension_name_reuse(self):
+        code = """
+            [x for x in [1]]
+            y = [x for _ in [1]]
+        """
+        self._check_in_scopes(code, {"y": [3]}, ns={"x": 3})
+
+        code = """
+            x = 2
+            [x for x in [1]]
+            y = [x for _ in [1]]
+        """
+        self._check_in_scopes(code, {"x": 2, "y": [3]}, ns={"x": 3}, scopes=["class"])
+        self._check_in_scopes(code, {"x": 2, "y": [2]}, ns={"x": 3}, scopes=["function", "module"])
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_exception_locations(self):
+        # The location of an exception raised from __init__ or
+        # __next__ should should be the iterator expression
+
+        def init_raises():
+            try:
+                [x for x in BrokenIter(init_raises=True)]
+            except Exception as e:
+                return e
+
+        def next_raises():
+            try:
+                [x for x in BrokenIter(next_raises=True)]
+            except Exception as e:
+                return e
+
+        def iter_raises():
+            try:
+                [x for x in BrokenIter(iter_raises=True)]
+            except Exception as e:
+                return e
+
+        for func, expected in [(init_raises, "BrokenIter(init_raises=True)"),
+                               (next_raises, "BrokenIter(next_raises=True)"),
+                               (iter_raises, "BrokenIter(iter_raises=True)"),
+                               ]:
+            with self.subTest(func):
+                exc = func()
+                f = traceback.extract_tb(exc.__traceback__)[0]
+                indent = 16
+                co = func.__code__
+                self.assertEqual(f.lineno, co.co_firstlineno + 2)
+                self.assertEqual(f.end_lineno, co.co_firstlineno + 2)
+                self.assertEqual(f.line[f.colno - indent : f.end_colno - indent],
+                                 expected)
+
 __test__ = {'doctests' : doctests}
 
 def load_tests(loader, tests, pattern):
diff --git a/Lib/test/test_logging.py b/Lib/test/test_logging.py
new file mode 100644
index 0000000000..a570d65f6c
--- /dev/null
+++ b/Lib/test/test_logging.py
@@ -0,0 +1,7049 @@
+# Copyright 2001-2022 by Vinay Sajip. All Rights Reserved.
+#
+# Permission to use, copy, modify, and distribute this software and its
+# documentation for any purpose and without fee is hereby granted,
+# provided that the above copyright notice appear in all copies and that
+# both that copyright notice and this permission notice appear in
+# supporting documentation, and that the name of Vinay Sajip
+# not be used in advertising or publicity pertaining to distribution
+# of the software without specific, written prior permission.
+# VINAY SAJIP DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+# ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+# VINAY SAJIP BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+# ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
+# IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
+# OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+"""Test harness for the logging module. Run all tests.
+
+Copyright (C) 2001-2022 Vinay Sajip. All Rights Reserved.
+"""
+import logging
+import logging.handlers
+import logging.config
+
+import codecs
+import configparser
+import copy
+import datetime
+import pathlib
+import pickle
+import io
+import itertools
+import gc
+import json
+import os
+import queue
+import random
+import re
+import shutil
+import socket
+import struct
+import sys
+import tempfile
+from test.support.script_helper import assert_python_ok, assert_python_failure
+from test import support
+from test.support import import_helper
+from test.support import os_helper
+from test.support import socket_helper
+from test.support import threading_helper
+from test.support import warnings_helper
+from test.support import asyncore
+from test.support import smtpd
+from test.support.logging_helper import TestHandler
+import textwrap
+import threading
+import asyncio
+import time
+import unittest
+import warnings
+import weakref
+
+from http.server import HTTPServer, BaseHTTPRequestHandler
+from unittest.mock import patch
+from urllib.parse import urlparse, parse_qs
+from socketserver import (ThreadingUDPServer, DatagramRequestHandler,
+                          ThreadingTCPServer, StreamRequestHandler)
+
+try:
+    import win32evtlog, win32evtlogutil, pywintypes
+except ImportError:
+    win32evtlog = win32evtlogutil = pywintypes = None
+
+try:
+    import zlib
+except ImportError:
+    pass
+
+
+# gh-89363: Skip fork() test if Python is built with Address Sanitizer (ASAN)
+# to work around a libasan race condition, dead lock in pthread_create().
+skip_if_asan_fork = unittest.skipIf(
+    support.HAVE_ASAN_FORK_BUG,
+    "libasan has a pthread_create() dead lock related to thread+fork")
+skip_if_tsan_fork = unittest.skipIf(
+    support.check_sanitizer(thread=True),
+    "TSAN doesn't support threads after fork")
+
+
+class BaseTest(unittest.TestCase):
+
+    """Base class for logging tests."""
+
+    log_format = "%(name)s -> %(levelname)s: %(message)s"
+    expected_log_pat = r"^([\w.]+) -> (\w+): (\d+)$"
+    message_num = 0
+
+    def setUp(self):
+        """Setup the default logging stream to an internal StringIO instance,
+        so that we can examine log output as we want."""
+        self._threading_key = threading_helper.threading_setup()
+
+        logger_dict = logging.getLogger().manager.loggerDict
+        logging._acquireLock()
+        try:
+            self.saved_handlers = logging._handlers.copy()
+            self.saved_handler_list = logging._handlerList[:]
+            self.saved_loggers = saved_loggers = logger_dict.copy()
+            self.saved_name_to_level = logging._nameToLevel.copy()
+            self.saved_level_to_name = logging._levelToName.copy()
+            self.logger_states = logger_states = {}
+            for name in saved_loggers:
+                logger_states[name] = getattr(saved_loggers[name],
+                                              'disabled', None)
+        finally:
+            logging._releaseLock()
+
+        # Set two unused loggers
+        self.logger1 = logging.getLogger("\xab\xd7\xbb")
+        self.logger2 = logging.getLogger("\u013f\u00d6\u0047")
+
+        self.root_logger = logging.getLogger("")
+        self.original_logging_level = self.root_logger.getEffectiveLevel()
+
+        self.stream = io.StringIO()
+        self.root_logger.setLevel(logging.DEBUG)
+        self.root_hdlr = logging.StreamHandler(self.stream)
+        self.root_formatter = logging.Formatter(self.log_format)
+        self.root_hdlr.setFormatter(self.root_formatter)
+        if self.logger1.hasHandlers():
+            hlist = self.logger1.handlers + self.root_logger.handlers
+            raise AssertionError('Unexpected handlers: %s' % hlist)
+        if self.logger2.hasHandlers():
+            hlist = self.logger2.handlers + self.root_logger.handlers
+            raise AssertionError('Unexpected handlers: %s' % hlist)
+        self.root_logger.addHandler(self.root_hdlr)
+        self.assertTrue(self.logger1.hasHandlers())
+        self.assertTrue(self.logger2.hasHandlers())
+
+    def tearDown(self):
+        """Remove our logging stream, and restore the original logging
+        level."""
+        self.stream.close()
+        self.root_logger.removeHandler(self.root_hdlr)
+        while self.root_logger.handlers:
+            h = self.root_logger.handlers[0]
+            self.root_logger.removeHandler(h)
+            h.close()
+        self.root_logger.setLevel(self.original_logging_level)
+        logging._acquireLock()
+        try:
+            logging._levelToName.clear()
+            logging._levelToName.update(self.saved_level_to_name)
+            logging._nameToLevel.clear()
+            logging._nameToLevel.update(self.saved_name_to_level)
+            logging._handlers.clear()
+            logging._handlers.update(self.saved_handlers)
+            logging._handlerList[:] = self.saved_handler_list
+            manager = logging.getLogger().manager
+            manager.disable = 0
+            loggerDict = manager.loggerDict
+            loggerDict.clear()
+            loggerDict.update(self.saved_loggers)
+            logger_states = self.logger_states
+            for name in self.logger_states:
+                if logger_states[name] is not None:
+                    self.saved_loggers[name].disabled = logger_states[name]
+        finally:
+            logging._releaseLock()
+
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self._threading_key)
+
+    def assert_log_lines(self, expected_values, stream=None, pat=None):
+        """Match the collected log lines against the regular expression
+        self.expected_log_pat, and compare the extracted group values to
+        the expected_values list of tuples."""
+        stream = stream or self.stream
+        pat = re.compile(pat or self.expected_log_pat)
+        actual_lines = stream.getvalue().splitlines()
+        self.assertEqual(len(actual_lines), len(expected_values))
+        for actual, expected in zip(actual_lines, expected_values):
+            match = pat.search(actual)
+            if not match:
+                self.fail("Log line does not match expected pattern:\n" +
+                          actual)
+            self.assertEqual(tuple(match.groups()), expected)
+        s = stream.read()
+        if s:
+            self.fail("Remaining output at end of log stream:\n" + s)
+
+    def next_message(self):
+        """Generate a message consisting solely of an auto-incrementing
+        integer."""
+        self.message_num += 1
+        return "%d" % self.message_num
+
+
+class BuiltinLevelsTest(BaseTest):
+    """Test builtin levels and their inheritance."""
+
+    def test_flat(self):
+        # Logging levels in a flat logger namespace.
+        m = self.next_message
+
+        ERR = logging.getLogger("ERR")
+        ERR.setLevel(logging.ERROR)
+        INF = logging.LoggerAdapter(logging.getLogger("INF"), {})
+        INF.setLevel(logging.INFO)
+        DEB = logging.getLogger("DEB")
+        DEB.setLevel(logging.DEBUG)
+
+        # These should log.
+        ERR.log(logging.CRITICAL, m())
+        ERR.error(m())
+
+        INF.log(logging.CRITICAL, m())
+        INF.error(m())
+        INF.warning(m())
+        INF.info(m())
+
+        DEB.log(logging.CRITICAL, m())
+        DEB.error(m())
+        DEB.warning(m())
+        DEB.info(m())
+        DEB.debug(m())
+
+        # These should not log.
+        ERR.warning(m())
+        ERR.info(m())
+        ERR.debug(m())
+
+        INF.debug(m())
+
+        self.assert_log_lines([
+            ('ERR', 'CRITICAL', '1'),
+            ('ERR', 'ERROR', '2'),
+            ('INF', 'CRITICAL', '3'),
+            ('INF', 'ERROR', '4'),
+            ('INF', 'WARNING', '5'),
+            ('INF', 'INFO', '6'),
+            ('DEB', 'CRITICAL', '7'),
+            ('DEB', 'ERROR', '8'),
+            ('DEB', 'WARNING', '9'),
+            ('DEB', 'INFO', '10'),
+            ('DEB', 'DEBUG', '11'),
+        ])
+
+    def test_nested_explicit(self):
+        # Logging levels in a nested namespace, all explicitly set.
+        m = self.next_message
+
+        INF = logging.getLogger("INF")
+        INF.setLevel(logging.INFO)
+        INF_ERR  = logging.getLogger("INF.ERR")
+        INF_ERR.setLevel(logging.ERROR)
+
+        # These should log.
+        INF_ERR.log(logging.CRITICAL, m())
+        INF_ERR.error(m())
+
+        # These should not log.
+        INF_ERR.warning(m())
+        INF_ERR.info(m())
+        INF_ERR.debug(m())
+
+        self.assert_log_lines([
+            ('INF.ERR', 'CRITICAL', '1'),
+            ('INF.ERR', 'ERROR', '2'),
+        ])
+
+    def test_nested_inherited(self):
+        # Logging levels in a nested namespace, inherited from parent loggers.
+        m = self.next_message
+
+        INF = logging.getLogger("INF")
+        INF.setLevel(logging.INFO)
+        INF_ERR  = logging.getLogger("INF.ERR")
+        INF_ERR.setLevel(logging.ERROR)
+        INF_UNDEF = logging.getLogger("INF.UNDEF")
+        INF_ERR_UNDEF = logging.getLogger("INF.ERR.UNDEF")
+        UNDEF = logging.getLogger("UNDEF")
+
+        # These should log.
+        INF_UNDEF.log(logging.CRITICAL, m())
+        INF_UNDEF.error(m())
+        INF_UNDEF.warning(m())
+        INF_UNDEF.info(m())
+        INF_ERR_UNDEF.log(logging.CRITICAL, m())
+        INF_ERR_UNDEF.error(m())
+
+        # These should not log.
+        INF_UNDEF.debug(m())
+        INF_ERR_UNDEF.warning(m())
+        INF_ERR_UNDEF.info(m())
+        INF_ERR_UNDEF.debug(m())
+
+        self.assert_log_lines([
+            ('INF.UNDEF', 'CRITICAL', '1'),
+            ('INF.UNDEF', 'ERROR', '2'),
+            ('INF.UNDEF', 'WARNING', '3'),
+            ('INF.UNDEF', 'INFO', '4'),
+            ('INF.ERR.UNDEF', 'CRITICAL', '5'),
+            ('INF.ERR.UNDEF', 'ERROR', '6'),
+        ])
+
+    def test_nested_with_virtual_parent(self):
+        # Logging levels when some parent does not exist yet.
+        m = self.next_message
+
+        INF = logging.getLogger("INF")
+        GRANDCHILD = logging.getLogger("INF.BADPARENT.UNDEF")
+        CHILD = logging.getLogger("INF.BADPARENT")
+        INF.setLevel(logging.INFO)
+
+        # These should log.
+        GRANDCHILD.log(logging.FATAL, m())
+        GRANDCHILD.info(m())
+        CHILD.log(logging.FATAL, m())
+        CHILD.info(m())
+
+        # These should not log.
+        GRANDCHILD.debug(m())
+        CHILD.debug(m())
+
+        self.assert_log_lines([
+            ('INF.BADPARENT.UNDEF', 'CRITICAL', '1'),
+            ('INF.BADPARENT.UNDEF', 'INFO', '2'),
+            ('INF.BADPARENT', 'CRITICAL', '3'),
+            ('INF.BADPARENT', 'INFO', '4'),
+        ])
+
+    def test_regression_22386(self):
+        """See issue #22386 for more information."""
+        self.assertEqual(logging.getLevelName('INFO'), logging.INFO)
+        self.assertEqual(logging.getLevelName(logging.INFO), 'INFO')
+
+    def test_issue27935(self):
+        fatal = logging.getLevelName('FATAL')
+        self.assertEqual(fatal, logging.FATAL)
+
+    def test_regression_29220(self):
+        """See issue #29220 for more information."""
+        logging.addLevelName(logging.INFO, '')
+        self.addCleanup(logging.addLevelName, logging.INFO, 'INFO')
+        self.assertEqual(logging.getLevelName(logging.INFO), '')
+        self.assertEqual(logging.getLevelName(logging.NOTSET), 'NOTSET')
+        self.assertEqual(logging.getLevelName('NOTSET'), logging.NOTSET)
+
+class BasicFilterTest(BaseTest):
+
+    """Test the bundled Filter class."""
+
+    def test_filter(self):
+        # Only messages satisfying the specified criteria pass through the
+        #  filter.
+        filter_ = logging.Filter("spam.eggs")
+        handler = self.root_logger.handlers[0]
+        try:
+            handler.addFilter(filter_)
+            spam = logging.getLogger("spam")
+            spam_eggs = logging.getLogger("spam.eggs")
+            spam_eggs_fish = logging.getLogger("spam.eggs.fish")
+            spam_bakedbeans = logging.getLogger("spam.bakedbeans")
+
+            spam.info(self.next_message())
+            spam_eggs.info(self.next_message())  # Good.
+            spam_eggs_fish.info(self.next_message())  # Good.
+            spam_bakedbeans.info(self.next_message())
+
+            self.assert_log_lines([
+                ('spam.eggs', 'INFO', '2'),
+                ('spam.eggs.fish', 'INFO', '3'),
+            ])
+        finally:
+            handler.removeFilter(filter_)
+
+    def test_callable_filter(self):
+        # Only messages satisfying the specified criteria pass through the
+        #  filter.
+
+        def filterfunc(record):
+            parts = record.name.split('.')
+            prefix = '.'.join(parts[:2])
+            return prefix == 'spam.eggs'
+
+        handler = self.root_logger.handlers[0]
+        try:
+            handler.addFilter(filterfunc)
+            spam = logging.getLogger("spam")
+            spam_eggs = logging.getLogger("spam.eggs")
+            spam_eggs_fish = logging.getLogger("spam.eggs.fish")
+            spam_bakedbeans = logging.getLogger("spam.bakedbeans")
+
+            spam.info(self.next_message())
+            spam_eggs.info(self.next_message())  # Good.
+            spam_eggs_fish.info(self.next_message())  # Good.
+            spam_bakedbeans.info(self.next_message())
+
+            self.assert_log_lines([
+                ('spam.eggs', 'INFO', '2'),
+                ('spam.eggs.fish', 'INFO', '3'),
+            ])
+        finally:
+            handler.removeFilter(filterfunc)
+
+    def test_empty_filter(self):
+        f = logging.Filter()
+        r = logging.makeLogRecord({'name': 'spam.eggs'})
+        self.assertTrue(f.filter(r))
+
+#
+#   First, we define our levels. There can be as many as you want - the only
+#     limitations are that they should be integers, the lowest should be > 0 and
+#   larger values mean less information being logged. If you need specific
+#   level values which do not fit into these limitations, you can use a
+#   mapping dictionary to convert between your application levels and the
+#   logging system.
+#
+SILENT      = 120
+TACITURN    = 119
+TERSE       = 118
+EFFUSIVE    = 117
+SOCIABLE    = 116
+VERBOSE     = 115
+TALKATIVE   = 114
+GARRULOUS   = 113
+CHATTERBOX  = 112
+BORING      = 111
+
+LEVEL_RANGE = range(BORING, SILENT + 1)
+
+#
+#   Next, we define names for our levels. You don't need to do this - in which
+#   case the system will use "Level n" to denote the text for the level.
+#
+my_logging_levels = {
+    SILENT      : 'Silent',
+    TACITURN    : 'Taciturn',
+    TERSE       : 'Terse',
+    EFFUSIVE    : 'Effusive',
+    SOCIABLE    : 'Sociable',
+    VERBOSE     : 'Verbose',
+    TALKATIVE   : 'Talkative',
+    GARRULOUS   : 'Garrulous',
+    CHATTERBOX  : 'Chatterbox',
+    BORING      : 'Boring',
+}
+
+class GarrulousFilter(logging.Filter):
+
+    """A filter which blocks garrulous messages."""
+
+    def filter(self, record):
+        return record.levelno != GARRULOUS
+
+class VerySpecificFilter(logging.Filter):
+
+    """A filter which blocks sociable and taciturn messages."""
+
+    def filter(self, record):
+        return record.levelno not in [SOCIABLE, TACITURN]
+
+
+class CustomLevelsAndFiltersTest(BaseTest):
+
+    """Test various filtering possibilities with custom logging levels."""
+
+    # Skip the logger name group.
+    expected_log_pat = r"^[\w.]+ -> (\w+): (\d+)$"
+
+    def setUp(self):
+        BaseTest.setUp(self)
+        for k, v in my_logging_levels.items():
+            logging.addLevelName(k, v)
+
+    def log_at_all_levels(self, logger):
+        for lvl in LEVEL_RANGE:
+            logger.log(lvl, self.next_message())
+
+    def test_handler_filter_replaces_record(self):
+        def replace_message(record: logging.LogRecord):
+            record = copy.copy(record)
+            record.msg = "new message!"
+            return record
+
+        # Set up a logging hierarchy such that "child" and it's handler
+        # (and thus `replace_message()`) always get called before
+        # propagating up to "parent".
+        # Then we can confirm that `replace_message()` was able to
+        # replace the log record without having a side effect on
+        # other loggers or handlers.
+        parent = logging.getLogger("parent")
+        child = logging.getLogger("parent.child")
+        stream_1 = io.StringIO()
+        stream_2 = io.StringIO()
+        handler_1 = logging.StreamHandler(stream_1)
+        handler_2 = logging.StreamHandler(stream_2)
+        handler_2.addFilter(replace_message)
+        parent.addHandler(handler_1)
+        child.addHandler(handler_2)
+
+        child.info("original message")
+        handler_1.flush()
+        handler_2.flush()
+        self.assertEqual(stream_1.getvalue(), "original message\n")
+        self.assertEqual(stream_2.getvalue(), "new message!\n")
+
+    def test_logging_filter_replaces_record(self):
+        records = set()
+
+        class RecordingFilter(logging.Filter):
+            def filter(self, record: logging.LogRecord):
+                records.add(id(record))
+                return copy.copy(record)
+
+        logger = logging.getLogger("logger")
+        logger.setLevel(logging.INFO)
+        logger.addFilter(RecordingFilter())
+        logger.addFilter(RecordingFilter())
+
+        logger.info("msg")
+
+        self.assertEqual(2, len(records))
+
+    def test_logger_filter(self):
+        # Filter at logger level.
+        self.root_logger.setLevel(VERBOSE)
+        # Levels >= 'Verbose' are good.
+        self.log_at_all_levels(self.root_logger)
+        self.assert_log_lines([
+            ('Verbose', '5'),
+            ('Sociable', '6'),
+            ('Effusive', '7'),
+            ('Terse', '8'),
+            ('Taciturn', '9'),
+            ('Silent', '10'),
+        ])
+
+    def test_handler_filter(self):
+        # Filter at handler level.
+        self.root_logger.handlers[0].setLevel(SOCIABLE)
+        try:
+            # Levels >= 'Sociable' are good.
+            self.log_at_all_levels(self.root_logger)
+            self.assert_log_lines([
+                ('Sociable', '6'),
+                ('Effusive', '7'),
+                ('Terse', '8'),
+                ('Taciturn', '9'),
+                ('Silent', '10'),
+            ])
+        finally:
+            self.root_logger.handlers[0].setLevel(logging.NOTSET)
+
+    def test_specific_filters(self):
+        # Set a specific filter object on the handler, and then add another
+        #  filter object on the logger itself.
+        handler = self.root_logger.handlers[0]
+        specific_filter = None
+        garr = GarrulousFilter()
+        handler.addFilter(garr)
+        try:
+            self.log_at_all_levels(self.root_logger)
+            first_lines = [
+                # Notice how 'Garrulous' is missing
+                ('Boring', '1'),
+                ('Chatterbox', '2'),
+                ('Talkative', '4'),
+                ('Verbose', '5'),
+                ('Sociable', '6'),
+                ('Effusive', '7'),
+                ('Terse', '8'),
+                ('Taciturn', '9'),
+                ('Silent', '10'),
+            ]
+            self.assert_log_lines(first_lines)
+
+            specific_filter = VerySpecificFilter()
+            self.root_logger.addFilter(specific_filter)
+            self.log_at_all_levels(self.root_logger)
+            self.assert_log_lines(first_lines + [
+                # Not only 'Garrulous' is still missing, but also 'Sociable'
+                # and 'Taciturn'
+                ('Boring', '11'),
+                ('Chatterbox', '12'),
+                ('Talkative', '14'),
+                ('Verbose', '15'),
+                ('Effusive', '17'),
+                ('Terse', '18'),
+                ('Silent', '20'),
+            ])
+        finally:
+            if specific_filter:
+                self.root_logger.removeFilter(specific_filter)
+            handler.removeFilter(garr)
+
+
+def make_temp_file(*args, **kwargs):
+    fd, fn = tempfile.mkstemp(*args, **kwargs)
+    os.close(fd)
+    return fn
+
+
+class HandlerTest(BaseTest):
+    def test_name(self):
+        h = logging.Handler()
+        h.name = 'generic'
+        self.assertEqual(h.name, 'generic')
+        h.name = 'anothergeneric'
+        self.assertEqual(h.name, 'anothergeneric')
+        self.assertRaises(NotImplementedError, h.emit, None)
+
+    def test_builtin_handlers(self):
+        # We can't actually *use* too many handlers in the tests,
+        # but we can try instantiating them with various options
+        if sys.platform in ('linux', 'darwin'):
+            for existing in (True, False):
+                fn = make_temp_file()
+                if not existing:
+                    os.unlink(fn)
+                h = logging.handlers.WatchedFileHandler(fn, encoding='utf-8', delay=True)
+                if existing:
+                    dev, ino = h.dev, h.ino
+                    self.assertEqual(dev, -1)
+                    self.assertEqual(ino, -1)
+                    r = logging.makeLogRecord({'msg': 'Test'})
+                    h.handle(r)
+                    # Now remove the file.
+                    os.unlink(fn)
+                    self.assertFalse(os.path.exists(fn))
+                    # The next call should recreate the file.
+                    h.handle(r)
+                    self.assertTrue(os.path.exists(fn))
+                else:
+                    self.assertEqual(h.dev, -1)
+                    self.assertEqual(h.ino, -1)
+                h.close()
+                if existing:
+                    os.unlink(fn)
+            if sys.platform == 'darwin':
+                sockname = '/var/run/syslog'
+            else:
+                sockname = '/dev/log'
+            try:
+                h = logging.handlers.SysLogHandler(sockname)
+                self.assertEqual(h.facility, h.LOG_USER)
+                self.assertTrue(h.unixsocket)
+                h.close()
+            except OSError: # syslogd might not be available
+                pass
+        for method in ('GET', 'POST', 'PUT'):
+            if method == 'PUT':
+                self.assertRaises(ValueError, logging.handlers.HTTPHandler,
+                                  'localhost', '/log', method)
+            else:
+                h = logging.handlers.HTTPHandler('localhost', '/log', method)
+                h.close()
+        h = logging.handlers.BufferingHandler(0)
+        r = logging.makeLogRecord({})
+        self.assertTrue(h.shouldFlush(r))
+        h.close()
+        h = logging.handlers.BufferingHandler(1)
+        self.assertFalse(h.shouldFlush(r))
+        h.close()
+
+    def test_pathlike_objects(self):
+        """
+        Test that path-like objects are accepted as filename arguments to handlers.
+
+        See Issue #27493.
+        """
+        fn = make_temp_file()
+        os.unlink(fn)
+        pfn = os_helper.FakePath(fn)
+        cases = (
+            (logging.FileHandler, (pfn, 'w')),
+            (logging.handlers.RotatingFileHandler, (pfn, 'a')),
+            (logging.handlers.TimedRotatingFileHandler, (pfn, 'h')),
+        )
+        if sys.platform in ('linux', 'darwin'):
+            cases += ((logging.handlers.WatchedFileHandler, (pfn, 'w')),)
+        for cls, args in cases:
+            h = cls(*args, encoding="utf-8")
+            self.assertTrue(os.path.exists(fn))
+            h.close()
+            os.unlink(fn)
+
+    @unittest.skipIf(os.name == 'nt', 'WatchedFileHandler not appropriate for Windows.')
+    @unittest.skipIf(
+        support.is_emscripten, "Emscripten cannot fstat unlinked files."
+    )
+    @threading_helper.requires_working_threading()
+    @support.requires_resource('walltime')
+    def test_race(self):
+        # Issue #14632 refers.
+        def remove_loop(fname, tries):
+            for _ in range(tries):
+                try:
+                    os.unlink(fname)
+                    self.deletion_time = time.time()
+                except OSError:
+                    pass
+                time.sleep(0.004 * random.randint(0, 4))
+
+        del_count = 500
+        log_count = 500
+
+        self.handle_time = None
+        self.deletion_time = None
+
+        for delay in (False, True):
+            fn = make_temp_file('.log', 'test_logging-3-')
+            remover = threading.Thread(target=remove_loop, args=(fn, del_count))
+            remover.daemon = True
+            remover.start()
+            h = logging.handlers.WatchedFileHandler(fn, encoding='utf-8', delay=delay)
+            f = logging.Formatter('%(asctime)s: %(levelname)s: %(message)s')
+            h.setFormatter(f)
+            try:
+                for _ in range(log_count):
+                    time.sleep(0.005)
+                    r = logging.makeLogRecord({'msg': 'testing' })
+                    try:
+                        self.handle_time = time.time()
+                        h.handle(r)
+                    except Exception:
+                        print('Deleted at %s, '
+                              'opened at %s' % (self.deletion_time,
+                                                self.handle_time))
+                        raise
+            finally:
+                remover.join()
+                h.close()
+                if os.path.exists(fn):
+                    os.unlink(fn)
+
+    # The implementation relies on os.register_at_fork existing, but we test
+    # based on os.fork existing because that is what users and this test use.
+    # This helps ensure that when fork exists (the important concept) that the
+    # register_at_fork mechanism is also present and used.
+    @support.requires_fork()
+    @threading_helper.requires_working_threading()
+    @skip_if_asan_fork
+    @skip_if_tsan_fork
+    def test_post_fork_child_no_deadlock(self):
+        """Ensure child logging locks are not held; bpo-6721 & bpo-36533."""
+        class _OurHandler(logging.Handler):
+            def __init__(self):
+                super().__init__()
+                self.sub_handler = logging.StreamHandler(
+                    stream=open('/dev/null', 'wt', encoding='utf-8'))
+
+            def emit(self, record):
+                self.sub_handler.acquire()
+                try:
+                    self.sub_handler.emit(record)
+                finally:
+                    self.sub_handler.release()
+
+        self.assertEqual(len(logging._handlers), 0)
+        refed_h = _OurHandler()
+        self.addCleanup(refed_h.sub_handler.stream.close)
+        refed_h.name = 'because we need at least one for this test'
+        self.assertGreater(len(logging._handlers), 0)
+        self.assertGreater(len(logging._at_fork_reinit_lock_weakset), 1)
+        test_logger = logging.getLogger('test_post_fork_child_no_deadlock')
+        test_logger.addHandler(refed_h)
+        test_logger.setLevel(logging.DEBUG)
+
+        locks_held__ready_to_fork = threading.Event()
+        fork_happened__release_locks_and_end_thread = threading.Event()
+
+        def lock_holder_thread_fn():
+            logging._acquireLock()
+            try:
+                refed_h.acquire()
+                try:
+                    # Tell the main thread to do the fork.
+                    locks_held__ready_to_fork.set()
+
+                    # If the deadlock bug exists, the fork will happen
+                    # without dealing with the locks we hold, deadlocking
+                    # the child.
+
+                    # Wait for a successful fork or an unreasonable amount of
+                    # time before releasing our locks.  To avoid a timing based
+                    # test we'd need communication from os.fork() as to when it
+                    # has actually happened.  Given this is a regression test
+                    # for a fixed issue, potentially less reliably detecting
+                    # regression via timing is acceptable for simplicity.
+                    # The test will always take at least this long. :(
+                    fork_happened__release_locks_and_end_thread.wait(0.5)
+                finally:
+                    refed_h.release()
+            finally:
+                logging._releaseLock()
+
+        lock_holder_thread = threading.Thread(
+            target=lock_holder_thread_fn,
+            name='test_post_fork_child_no_deadlock lock holder')
+        lock_holder_thread.start()
+
+        locks_held__ready_to_fork.wait()
+        pid = os.fork()
+        if pid == 0:
+            # Child process
+            try:
+                test_logger.info(r'Child process did not deadlock. \o/')
+            finally:
+                os._exit(0)
+        else:
+            # Parent process
+            test_logger.info(r'Parent process returned from fork. \o/')
+            fork_happened__release_locks_and_end_thread.set()
+            lock_holder_thread.join()
+
+            support.wait_process(pid, exitcode=0)
+
+
+class BadStream(object):
+    def write(self, data):
+        raise RuntimeError('deliberate mistake')
+
+class TestStreamHandler(logging.StreamHandler):
+    def handleError(self, record):
+        self.error_record = record
+
+class StreamWithIntName(object):
+    level = logging.NOTSET
+    name = 2
+
+class StreamHandlerTest(BaseTest):
+    def test_error_handling(self):
+        h = TestStreamHandler(BadStream())
+        r = logging.makeLogRecord({})
+        old_raise = logging.raiseExceptions
+
+        try:
+            h.handle(r)
+            self.assertIs(h.error_record, r)
+
+            h = logging.StreamHandler(BadStream())
+            with support.captured_stderr() as stderr:
+                h.handle(r)
+                msg = '\nRuntimeError: deliberate mistake\n'
+                self.assertIn(msg, stderr.getvalue())
+
+            logging.raiseExceptions = False
+            with support.captured_stderr() as stderr:
+                h.handle(r)
+                self.assertEqual('', stderr.getvalue())
+        finally:
+            logging.raiseExceptions = old_raise
+
+    def test_stream_setting(self):
+        """
+        Test setting the handler's stream
+        """
+        h = logging.StreamHandler()
+        stream = io.StringIO()
+        old = h.setStream(stream)
+        self.assertIs(old, sys.stderr)
+        actual = h.setStream(old)
+        self.assertIs(actual, stream)
+        # test that setting to existing value returns None
+        actual = h.setStream(old)
+        self.assertIsNone(actual)
+
+    def test_can_represent_stream_with_int_name(self):
+        h = logging.StreamHandler(StreamWithIntName())
+        self.assertEqual(repr(h), '<StreamHandler 2 (NOTSET)>')
+
+# -- The following section could be moved into a server_helper.py module
+# -- if it proves to be of wider utility than just test_logging
+
+class TestSMTPServer(smtpd.SMTPServer):
+    """
+    This class implements a test SMTP server.
+
+    :param addr: A (host, port) tuple which the server listens on.
+                 You can specify a port value of zero: the server's
+                 *port* attribute will hold the actual port number
+                 used, which can be used in client connections.
+    :param handler: A callable which will be called to process
+                    incoming messages. The handler will be passed
+                    the client address tuple, who the message is from,
+                    a list of recipients and the message data.
+    :param poll_interval: The interval, in seconds, used in the underlying
+                          :func:`select` or :func:`poll` call by
+                          :func:`asyncore.loop`.
+    :param sockmap: A dictionary which will be used to hold
+                    :class:`asyncore.dispatcher` instances used by
+                    :func:`asyncore.loop`. This avoids changing the
+                    :mod:`asyncore` module's global state.
+    """
+
+    def __init__(self, addr, handler, poll_interval, sockmap):
+        smtpd.SMTPServer.__init__(self, addr, None, map=sockmap,
+                                  decode_data=True)
+        self.port = self.socket.getsockname()[1]
+        self._handler = handler
+        self._thread = None
+        self._quit = False
+        self.poll_interval = poll_interval
+
+    def process_message(self, peer, mailfrom, rcpttos, data):
+        """
+        Delegates to the handler passed in to the server's constructor.
+
+        Typically, this will be a test case method.
+        :param peer: The client (host, port) tuple.
+        :param mailfrom: The address of the sender.
+        :param rcpttos: The addresses of the recipients.
+        :param data: The message.
+        """
+        self._handler(peer, mailfrom, rcpttos, data)
+
+    def start(self):
+        """
+        Start the server running on a separate daemon thread.
+        """
+        self._thread = t = threading.Thread(target=self.serve_forever,
+                                            args=(self.poll_interval,))
+        t.daemon = True
+        t.start()
+
+    def serve_forever(self, poll_interval):
+        """
+        Run the :mod:`asyncore` loop until normal termination
+        conditions arise.
+        :param poll_interval: The interval, in seconds, used in the underlying
+                              :func:`select` or :func:`poll` call by
+                              :func:`asyncore.loop`.
+        """
+        while not self._quit:
+            asyncore.loop(poll_interval, map=self._map, count=1)
+
+    def stop(self):
+        """
+        Stop the thread by closing the server instance.
+        Wait for the server thread to terminate.
+        """
+        self._quit = True
+        threading_helper.join_thread(self._thread)
+        self._thread = None
+        self.close()
+        asyncore.close_all(map=self._map, ignore_all=True)
+
+
+class ControlMixin(object):
+    """
+    This mixin is used to start a server on a separate thread, and
+    shut it down programmatically. Request handling is simplified - instead
+    of needing to derive a suitable RequestHandler subclass, you just
+    provide a callable which will be passed each received request to be
+    processed.
+
+    :param handler: A handler callable which will be called with a
+                    single parameter - the request - in order to
+                    process the request. This handler is called on the
+                    server thread, effectively meaning that requests are
+                    processed serially. While not quite web scale ;-),
+                    this should be fine for testing applications.
+    :param poll_interval: The polling interval in seconds.
+    """
+    def __init__(self, handler, poll_interval):
+        self._thread = None
+        self.poll_interval = poll_interval
+        self._handler = handler
+        self.ready = threading.Event()
+
+    def start(self):
+        """
+        Create a daemon thread to run the server, and start it.
+        """
+        self._thread = t = threading.Thread(target=self.serve_forever,
+                                            args=(self.poll_interval,))
+        t.daemon = True
+        t.start()
+
+    def serve_forever(self, poll_interval):
+        """
+        Run the server. Set the ready flag before entering the
+        service loop.
+        """
+        self.ready.set()
+        super(ControlMixin, self).serve_forever(poll_interval)
+
+    def stop(self):
+        """
+        Tell the server thread to stop, and wait for it to do so.
+        """
+        self.shutdown()
+        if self._thread is not None:
+            threading_helper.join_thread(self._thread)
+            self._thread = None
+        self.server_close()
+        self.ready.clear()
+
+class TestHTTPServer(ControlMixin, HTTPServer):
+    """
+    An HTTP server which is controllable using :class:`ControlMixin`.
+
+    :param addr: A tuple with the IP address and port to listen on.
+    :param handler: A handler callable which will be called with a
+                    single parameter - the request - in order to
+                    process the request.
+    :param poll_interval: The polling interval in seconds.
+    :param log: Pass ``True`` to enable log messages.
+    """
+    def __init__(self, addr, handler, poll_interval=0.5,
+                 log=False, sslctx=None):
+        class DelegatingHTTPRequestHandler(BaseHTTPRequestHandler):
+            def __getattr__(self, name, default=None):
+                if name.startswith('do_'):
+                    return self.process_request
+                raise AttributeError(name)
+
+            def process_request(self):
+                self.server._handler(self)
+
+            def log_message(self, format, *args):
+                if log:
+                    super(DelegatingHTTPRequestHandler,
+                          self).log_message(format, *args)
+        HTTPServer.__init__(self, addr, DelegatingHTTPRequestHandler)
+        ControlMixin.__init__(self, handler, poll_interval)
+        self.sslctx = sslctx
+
+    def get_request(self):
+        try:
+            sock, addr = self.socket.accept()
+            if self.sslctx:
+                sock = self.sslctx.wrap_socket(sock, server_side=True)
+        except OSError as e:
+            # socket errors are silenced by the caller, print them here
+            sys.stderr.write("Got an error:\n%s\n" % e)
+            raise
+        return sock, addr
+
+class TestTCPServer(ControlMixin, ThreadingTCPServer):
+    """
+    A TCP server which is controllable using :class:`ControlMixin`.
+
+    :param addr: A tuple with the IP address and port to listen on.
+    :param handler: A handler callable which will be called with a single
+                    parameter - the request - in order to process the request.
+    :param poll_interval: The polling interval in seconds.
+    :bind_and_activate: If True (the default), binds the server and starts it
+                        listening. If False, you need to call
+                        :meth:`server_bind` and :meth:`server_activate` at
+                        some later time before calling :meth:`start`, so that
+                        the server will set up the socket and listen on it.
+    """
+
+    allow_reuse_address = True
+
+    def __init__(self, addr, handler, poll_interval=0.5,
+                 bind_and_activate=True):
+        class DelegatingTCPRequestHandler(StreamRequestHandler):
+
+            def handle(self):
+                self.server._handler(self)
+        ThreadingTCPServer.__init__(self, addr, DelegatingTCPRequestHandler,
+                                    bind_and_activate)
+        ControlMixin.__init__(self, handler, poll_interval)
+
+    def server_bind(self):
+        super(TestTCPServer, self).server_bind()
+        self.port = self.socket.getsockname()[1]
+
+class TestUDPServer(ControlMixin, ThreadingUDPServer):
+    """
+    A UDP server which is controllable using :class:`ControlMixin`.
+
+    :param addr: A tuple with the IP address and port to listen on.
+    :param handler: A handler callable which will be called with a
+                    single parameter - the request - in order to
+                    process the request.
+    :param poll_interval: The polling interval for shutdown requests,
+                          in seconds.
+    :bind_and_activate: If True (the default), binds the server and
+                        starts it listening. If False, you need to
+                        call :meth:`server_bind` and
+                        :meth:`server_activate` at some later time
+                        before calling :meth:`start`, so that the server will
+                        set up the socket and listen on it.
+    """
+    def __init__(self, addr, handler, poll_interval=0.5,
+                 bind_and_activate=True):
+        class DelegatingUDPRequestHandler(DatagramRequestHandler):
+
+            def handle(self):
+                self.server._handler(self)
+
+            def finish(self):
+                data = self.wfile.getvalue()
+                if data:
+                    try:
+                        super(DelegatingUDPRequestHandler, self).finish()
+                    except OSError:
+                        if not self.server._closed:
+                            raise
+
+        ThreadingUDPServer.__init__(self, addr,
+                                    DelegatingUDPRequestHandler,
+                                    bind_and_activate)
+        ControlMixin.__init__(self, handler, poll_interval)
+        self._closed = False
+
+    def server_bind(self):
+        super(TestUDPServer, self).server_bind()
+        self.port = self.socket.getsockname()[1]
+
+    def server_close(self):
+        super(TestUDPServer, self).server_close()
+        self._closed = True
+
+if hasattr(socket, "AF_UNIX"):
+    class TestUnixStreamServer(TestTCPServer):
+        address_family = socket.AF_UNIX
+
+    class TestUnixDatagramServer(TestUDPServer):
+        address_family = socket.AF_UNIX
+
+# - end of server_helper section
+
+@support.requires_working_socket()
+@threading_helper.requires_working_threading()
+class SMTPHandlerTest(BaseTest):
+    # bpo-14314, bpo-19665, bpo-34092: don't wait forever
+    TIMEOUT = support.LONG_TIMEOUT
+
+    # TODO: RUSTPYTHON
+    @unittest.skip(reason="Hangs RustPython")
+    def test_basic(self):
+        sockmap = {}
+        server = TestSMTPServer((socket_helper.HOST, 0), self.process_message, 0.001,
+                                sockmap)
+        server.start()
+        addr = (socket_helper.HOST, server.port)
+        h = logging.handlers.SMTPHandler(addr, 'me', 'you', 'Log',
+                                         timeout=self.TIMEOUT)
+        self.assertEqual(h.toaddrs, ['you'])
+        self.messages = []
+        r = logging.makeLogRecord({'msg': 'Hello \u2713'})
+        self.handled = threading.Event()
+        h.handle(r)
+        self.handled.wait(self.TIMEOUT)
+        server.stop()
+        self.assertTrue(self.handled.is_set())
+        self.assertEqual(len(self.messages), 1)
+        peer, mailfrom, rcpttos, data = self.messages[0]
+        self.assertEqual(mailfrom, 'me')
+        self.assertEqual(rcpttos, ['you'])
+        self.assertIn('\nSubject: Log\n', data)
+        self.assertTrue(data.endswith('\n\nHello \u2713'))
+        h.close()
+
+    def process_message(self, *args):
+        self.messages.append(args)
+        self.handled.set()
+
+class MemoryHandlerTest(BaseTest):
+
+    """Tests for the MemoryHandler."""
+
+    # Do not bother with a logger name group.
+    expected_log_pat = r"^[\w.]+ -> (\w+): (\d+)$"
+
+    def setUp(self):
+        BaseTest.setUp(self)
+        self.mem_hdlr = logging.handlers.MemoryHandler(10, logging.WARNING,
+                                                       self.root_hdlr)
+        self.mem_logger = logging.getLogger('mem')
+        self.mem_logger.propagate = 0
+        self.mem_logger.addHandler(self.mem_hdlr)
+
+    def tearDown(self):
+        self.mem_hdlr.close()
+        BaseTest.tearDown(self)
+
+    def test_flush(self):
+        # The memory handler flushes to its target handler based on specific
+        #  criteria (message count and message level).
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines([])
+        self.mem_logger.info(self.next_message())
+        self.assert_log_lines([])
+        # This will flush because the level is >= logging.WARNING
+        self.mem_logger.warning(self.next_message())
+        lines = [
+            ('DEBUG', '1'),
+            ('INFO', '2'),
+            ('WARNING', '3'),
+        ]
+        self.assert_log_lines(lines)
+        for n in (4, 14):
+            for i in range(9):
+                self.mem_logger.debug(self.next_message())
+            self.assert_log_lines(lines)
+            # This will flush because it's the 10th message since the last
+            #  flush.
+            self.mem_logger.debug(self.next_message())
+            lines = lines + [('DEBUG', str(i)) for i in range(n, n + 10)]
+            self.assert_log_lines(lines)
+
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines(lines)
+
+    def test_flush_on_close(self):
+        """
+        Test that the flush-on-close configuration works as expected.
+        """
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines([])
+        self.mem_logger.info(self.next_message())
+        self.assert_log_lines([])
+        self.mem_logger.removeHandler(self.mem_hdlr)
+        # Default behaviour is to flush on close. Check that it happens.
+        self.mem_hdlr.close()
+        lines = [
+            ('DEBUG', '1'),
+            ('INFO', '2'),
+        ]
+        self.assert_log_lines(lines)
+        # Now configure for flushing not to be done on close.
+        self.mem_hdlr = logging.handlers.MemoryHandler(10, logging.WARNING,
+                                                       self.root_hdlr,
+                                                       False)
+        self.mem_logger.addHandler(self.mem_hdlr)
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines(lines)  # no change
+        self.mem_logger.info(self.next_message())
+        self.assert_log_lines(lines)  # no change
+        self.mem_logger.removeHandler(self.mem_hdlr)
+        self.mem_hdlr.close()
+        # assert that no new lines have been added
+        self.assert_log_lines(lines)  # no change
+
+    def test_shutdown_flush_on_close(self):
+        """
+        Test that the flush-on-close configuration is respected by the
+        shutdown method.
+        """
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines([])
+        self.mem_logger.info(self.next_message())
+        self.assert_log_lines([])
+        # Default behaviour is to flush on close. Check that it happens.
+        logging.shutdown(handlerList=[logging.weakref.ref(self.mem_hdlr)])
+        lines = [
+            ('DEBUG', '1'),
+            ('INFO', '2'),
+        ]
+        self.assert_log_lines(lines)
+        # Now configure for flushing not to be done on close.
+        self.mem_hdlr = logging.handlers.MemoryHandler(10, logging.WARNING,
+                                                       self.root_hdlr,
+                                                       False)
+        self.mem_logger.addHandler(self.mem_hdlr)
+        self.mem_logger.debug(self.next_message())
+        self.assert_log_lines(lines)  # no change
+        self.mem_logger.info(self.next_message())
+        self.assert_log_lines(lines)  # no change
+        # assert that no new lines have been added after shutdown
+        logging.shutdown(handlerList=[logging.weakref.ref(self.mem_hdlr)])
+        self.assert_log_lines(lines) # no change
+
+    @threading_helper.requires_working_threading()
+    def test_race_between_set_target_and_flush(self):
+        class MockRaceConditionHandler:
+            def __init__(self, mem_hdlr):
+                self.mem_hdlr = mem_hdlr
+                self.threads = []
+
+            def removeTarget(self):
+                self.mem_hdlr.setTarget(None)
+
+            def handle(self, msg):
+                thread = threading.Thread(target=self.removeTarget)
+                self.threads.append(thread)
+                thread.start()
+
+        target = MockRaceConditionHandler(self.mem_hdlr)
+        try:
+            self.mem_hdlr.setTarget(target)
+
+            for _ in range(10):
+                time.sleep(0.005)
+                self.mem_logger.info("not flushed")
+                self.mem_logger.warning("flushed")
+        finally:
+            for thread in target.threads:
+                threading_helper.join_thread(thread)
+
+
+class ExceptionFormatter(logging.Formatter):
+    """A special exception formatter."""
+    def formatException(self, ei):
+        return "Got a [%s]" % ei[0].__name__
+
+def closeFileHandler(h, fn):
+    h.close()
+    os.remove(fn)
+
+class ConfigFileTest(BaseTest):
+
+    """Reading logging config from a .ini-style config file."""
+
+    check_no_resource_warning = warnings_helper.check_no_resource_warning
+    expected_log_pat = r"^(\w+) \+\+ (\w+)$"
+
+    # config0 is a standard configuration.
+    config0 = """
+    [loggers]
+    keys=root
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=WARNING
+    handlers=hand1
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [formatter_form1]
+    format=%(levelname)s ++ %(message)s
+    datefmt=
+    """
+
+    # config1 adds a little to the standard configuration.
+    config1 = """
+    [loggers]
+    keys=root,parser
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=WARNING
+    handlers=
+
+    [logger_parser]
+    level=DEBUG
+    handlers=hand1
+    propagate=1
+    qualname=compiler.parser
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [formatter_form1]
+    format=%(levelname)s ++ %(message)s
+    datefmt=
+    """
+
+    # config1a moves the handler to the root.
+    config1a = """
+    [loggers]
+    keys=root,parser
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=WARNING
+    handlers=hand1
+
+    [logger_parser]
+    level=DEBUG
+    handlers=
+    propagate=1
+    qualname=compiler.parser
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [formatter_form1]
+    format=%(levelname)s ++ %(message)s
+    datefmt=
+    """
+
+    # config2 has a subtle configuration error that should be reported
+    config2 = config1.replace("sys.stdout", "sys.stbout")
+
+    # config3 has a less subtle configuration error
+    config3 = config1.replace("formatter=form1", "formatter=misspelled_name")
+
+    # config4 specifies a custom formatter class to be loaded
+    config4 = """
+    [loggers]
+    keys=root
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=NOTSET
+    handlers=hand1
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [formatter_form1]
+    class=""" + __name__ + """.ExceptionFormatter
+    format=%(levelname)s:%(name)s:%(message)s
+    datefmt=
+    """
+
+    # config5 specifies a custom handler class to be loaded
+    config5 = config1.replace('class=StreamHandler', 'class=logging.StreamHandler')
+
+    # config6 uses ', ' delimiters in the handlers and formatters sections
+    config6 = """
+    [loggers]
+    keys=root,parser
+
+    [handlers]
+    keys=hand1, hand2
+
+    [formatters]
+    keys=form1, form2
+
+    [logger_root]
+    level=WARNING
+    handlers=
+
+    [logger_parser]
+    level=DEBUG
+    handlers=hand1
+    propagate=1
+    qualname=compiler.parser
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [handler_hand2]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stderr,)
+
+    [formatter_form1]
+    format=%(levelname)s ++ %(message)s
+    datefmt=
+
+    [formatter_form2]
+    format=%(message)s
+    datefmt=
+    """
+
+    # config7 adds a compiler logger, and uses kwargs instead of args.
+    config7 = """
+    [loggers]
+    keys=root,parser,compiler
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=WARNING
+    handlers=hand1
+
+    [logger_compiler]
+    level=DEBUG
+    handlers=
+    propagate=1
+    qualname=compiler
+
+    [logger_parser]
+    level=DEBUG
+    handlers=
+    propagate=1
+    qualname=compiler.parser
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    kwargs={'stream': sys.stdout,}
+
+    [formatter_form1]
+    format=%(levelname)s ++ %(message)s
+    datefmt=
+    """
+
+    # config 8, check for resource warning
+    config8 = r"""
+    [loggers]
+    keys=root
+
+    [handlers]
+    keys=file
+
+    [formatters]
+    keys=
+
+    [logger_root]
+    level=DEBUG
+    handlers=file
+
+    [handler_file]
+    class=FileHandler
+    level=DEBUG
+    args=("{tempfile}",)
+    kwargs={{"encoding": "utf-8"}}
+    """
+
+
+    config9 = """
+    [loggers]
+    keys=root
+
+    [handlers]
+    keys=hand1
+
+    [formatters]
+    keys=form1
+
+    [logger_root]
+    level=WARNING
+    handlers=hand1
+
+    [handler_hand1]
+    class=StreamHandler
+    level=NOTSET
+    formatter=form1
+    args=(sys.stdout,)
+
+    [formatter_form1]
+    format=%(message)s ++ %(customfield)s
+    defaults={"customfield": "defaultvalue"}
+    """
+
+    disable_test = """
+    [loggers]
+    keys=root
+
+    [handlers]
+    keys=screen
+
+    [formatters]
+    keys=
+
+    [logger_root]
+    level=DEBUG
+    handlers=screen
+
+    [handler_screen]
+    level=DEBUG
+    class=StreamHandler
+    args=(sys.stdout,)
+    formatter=
+    """
+
+    def apply_config(self, conf, **kwargs):
+        file = io.StringIO(textwrap.dedent(conf))
+        logging.config.fileConfig(file, encoding="utf-8", **kwargs)
+
+    def test_config0_ok(self):
+        # A simple config file which overrides the default settings.
+        with support.captured_stdout() as output:
+            self.apply_config(self.config0)
+            logger = logging.getLogger()
+            # Won't output anything
+            logger.info(self.next_message())
+            # Outputs a message
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config0_using_cp_ok(self):
+        # A simple config file which overrides the default settings.
+        with support.captured_stdout() as output:
+            file = io.StringIO(textwrap.dedent(self.config0))
+            cp = configparser.ConfigParser()
+            cp.read_file(file)
+            logging.config.fileConfig(cp)
+            logger = logging.getLogger()
+            # Won't output anything
+            logger.info(self.next_message())
+            # Outputs a message
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config1_ok(self, config=config1):
+        # A config file defining a sub-parser as well.
+        with support.captured_stdout() as output:
+            self.apply_config(config)
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config2_failure(self):
+        # A simple config file which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config2)
+
+    def test_config3_failure(self):
+        # A simple config file which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config3)
+
+    def test_config4_ok(self):
+        # A config file specifying a custom formatter class.
+        with support.captured_stdout() as output:
+            self.apply_config(self.config4)
+            logger = logging.getLogger()
+            try:
+                raise RuntimeError()
+            except RuntimeError:
+                logging.exception("just testing")
+            sys.stdout.seek(0)
+            self.assertEqual(output.getvalue(),
+                             "ERROR:root:just testing\nGot a [RuntimeError]\n")
+            # Original logger output is empty
+            self.assert_log_lines([])
+
+    def test_config5_ok(self):
+        self.test_config1_ok(config=self.config5)
+
+    def test_config6_ok(self):
+        self.test_config1_ok(config=self.config6)
+
+    def test_config7_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config1a)
+            logger = logging.getLogger("compiler.parser")
+            # See issue #11424. compiler-hyphenated sorts
+            # between compiler and compiler.xyz and this
+            # was preventing compiler.xyz from being included
+            # in the child loggers of compiler because of an
+            # overzealous loop termination condition.
+            hyphenated = logging.getLogger('compiler-hyphenated')
+            # All will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            hyphenated.critical(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+                ('CRITICAL', '3'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+        with support.captured_stdout() as output:
+            self.apply_config(self.config7)
+            logger = logging.getLogger("compiler.parser")
+            self.assertFalse(logger.disabled)
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            logger = logging.getLogger("compiler.lexer")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            # Will not appear
+            hyphenated.critical(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '4'),
+                ('ERROR', '5'),
+                ('INFO', '6'),
+                ('ERROR', '7'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config8_ok(self):
+
+        with self.check_no_resource_warning():
+            fn = make_temp_file(".log", "test_logging-X-")
+
+            # Replace single backslash with double backslash in windows
+            # to avoid unicode error during string formatting
+            if os.name == "nt":
+                fn = fn.replace("\\", "\\\\")
+
+            config8 = self.config8.format(tempfile=fn)
+
+            self.apply_config(config8)
+            self.apply_config(config8)
+
+        handler = logging.root.handlers[0]
+        self.addCleanup(closeFileHandler, handler, fn)
+
+    def test_config9_ok(self):
+        self.apply_config(self.config9)
+        formatter = logging.root.handlers[0].formatter
+        result = formatter.format(logging.makeLogRecord({'msg': 'test'}))
+        self.assertEqual(result, 'test ++ defaultvalue')
+        result = formatter.format(logging.makeLogRecord(
+            {'msg': 'test', 'customfield': "customvalue"}))
+        self.assertEqual(result, 'test ++ customvalue')
+
+
+    def test_logger_disabling(self):
+        self.apply_config(self.disable_test)
+        logger = logging.getLogger('some_pristine_logger')
+        self.assertFalse(logger.disabled)
+        self.apply_config(self.disable_test)
+        self.assertTrue(logger.disabled)
+        self.apply_config(self.disable_test, disable_existing_loggers=False)
+        self.assertFalse(logger.disabled)
+
+    def test_config_set_handler_names(self):
+        test_config = """
+            [loggers]
+            keys=root
+
+            [handlers]
+            keys=hand1
+
+            [formatters]
+            keys=form1
+
+            [logger_root]
+            handlers=hand1
+
+            [handler_hand1]
+            class=StreamHandler
+            formatter=form1
+
+            [formatter_form1]
+            format=%(levelname)s ++ %(message)s
+            """
+        self.apply_config(test_config)
+        self.assertEqual(logging.getLogger().handlers[0].name, 'hand1')
+
+    def test_exception_if_confg_file_is_invalid(self):
+        test_config = """
+            [loggers]
+            keys=root
+
+            [handlers]
+            keys=hand1
+
+            [formatters]
+            keys=form1
+
+            [logger_root]
+            handlers=hand1
+
+            [handler_hand1]
+            class=StreamHandler
+            formatter=form1
+
+            [formatter_form1]
+            format=%(levelname)s ++ %(message)s
+
+            prince
+            """
+
+        file = io.StringIO(textwrap.dedent(test_config))
+        self.assertRaises(RuntimeError, logging.config.fileConfig, file)
+
+    def test_exception_if_confg_file_is_empty(self):
+        fd, fn = tempfile.mkstemp(prefix='test_empty_', suffix='.ini')
+        os.close(fd)
+        self.assertRaises(RuntimeError, logging.config.fileConfig, fn)
+        os.remove(fn)
+
+    def test_exception_if_config_file_does_not_exist(self):
+        self.assertRaises(FileNotFoundError, logging.config.fileConfig, 'filenotfound')
+
+    def test_defaults_do_no_interpolation(self):
+        """bpo-33802 defaults should not get interpolated"""
+        ini = textwrap.dedent("""
+            [formatters]
+            keys=default
+
+            [formatter_default]
+
+            [handlers]
+            keys=console
+
+            [handler_console]
+            class=logging.StreamHandler
+            args=tuple()
+
+            [loggers]
+            keys=root
+
+            [logger_root]
+            formatter=default
+            handlers=console
+            """).strip()
+        fd, fn = tempfile.mkstemp(prefix='test_logging_', suffix='.ini')
+        try:
+            os.write(fd, ini.encode('ascii'))
+            os.close(fd)
+            logging.config.fileConfig(
+                fn,
+                encoding="utf-8",
+                defaults=dict(
+                    version=1,
+                    disable_existing_loggers=False,
+                    formatters={
+                        "generic": {
+                            "format": "%(asctime)s [%(process)d] [%(levelname)s] %(message)s",
+                            "datefmt": "[%Y-%m-%d %H:%M:%S %z]",
+                            "class": "logging.Formatter"
+                        },
+                    },
+                )
+            )
+        finally:
+            os.unlink(fn)
+
+
+@support.requires_working_socket()
+@threading_helper.requires_working_threading()
+class SocketHandlerTest(BaseTest):
+
+    """Test for SocketHandler objects."""
+
+    server_class = TestTCPServer
+    address = ('localhost', 0)
+
+    def setUp(self):
+        """Set up a TCP server to receive log messages, and a SocketHandler
+        pointing to that server's address and port."""
+        BaseTest.setUp(self)
+        # Issue #29177: deal with errors that happen during setup
+        self.server = self.sock_hdlr = self.server_exception = None
+        try:
+            self.server = server = self.server_class(self.address,
+                                                     self.handle_socket, 0.01)
+            server.start()
+            # Uncomment next line to test error recovery in setUp()
+            # raise OSError('dummy error raised')
+        except OSError as e:
+            self.server_exception = e
+            return
+        server.ready.wait()
+        hcls = logging.handlers.SocketHandler
+        if isinstance(server.server_address, tuple):
+            self.sock_hdlr = hcls('localhost', server.port)
+        else:
+            self.sock_hdlr = hcls(server.server_address, None)
+        self.log_output = ''
+        self.root_logger.removeHandler(self.root_logger.handlers[0])
+        self.root_logger.addHandler(self.sock_hdlr)
+        self.handled = threading.Semaphore(0)
+
+    def tearDown(self):
+        """Shutdown the TCP server."""
+        try:
+            if self.sock_hdlr:
+                self.root_logger.removeHandler(self.sock_hdlr)
+                self.sock_hdlr.close()
+            if self.server:
+                self.server.stop()
+        finally:
+            BaseTest.tearDown(self)
+
+    def handle_socket(self, request):
+        conn = request.connection
+        while True:
+            chunk = conn.recv(4)
+            if len(chunk) < 4:
+                break
+            slen = struct.unpack(">L", chunk)[0]
+            chunk = conn.recv(slen)
+            while len(chunk) < slen:
+                chunk = chunk + conn.recv(slen - len(chunk))
+            obj = pickle.loads(chunk)
+            record = logging.makeLogRecord(obj)
+            self.log_output += record.msg + '\n'
+            self.handled.release()
+
+    def test_output(self):
+        # The log message sent to the SocketHandler is properly received.
+        if self.server_exception:
+            self.skipTest(self.server_exception)
+        logger = logging.getLogger("tcp")
+        logger.error("spam")
+        self.handled.acquire()
+        logger.debug("eggs")
+        self.handled.acquire()
+        self.assertEqual(self.log_output, "spam\neggs\n")
+
+    def test_noserver(self):
+        if self.server_exception:
+            self.skipTest(self.server_exception)
+        # Avoid timing-related failures due to SocketHandler's own hard-wired
+        # one-second timeout on socket.create_connection() (issue #16264).
+        self.sock_hdlr.retryStart = 2.5
+        # Kill the server
+        self.server.stop()
+        # The logging call should try to connect, which should fail
+        try:
+            raise RuntimeError('Deliberate mistake')
+        except RuntimeError:
+            self.root_logger.exception('Never sent')
+        self.root_logger.error('Never sent, either')
+        now = time.time()
+        self.assertGreater(self.sock_hdlr.retryTime, now)
+        time.sleep(self.sock_hdlr.retryTime - now + 0.001)
+        self.root_logger.error('Nor this')
+
+
+@unittest.skipUnless(hasattr(socket, "AF_UNIX"), "Unix sockets required")
+class UnixSocketHandlerTest(SocketHandlerTest):
+
+    """Test for SocketHandler with unix sockets."""
+
+    if hasattr(socket, "AF_UNIX"):
+        server_class = TestUnixStreamServer
+
+    def setUp(self):
+        # override the definition in the base class
+        self.address = socket_helper.create_unix_domain_name()
+        self.addCleanup(os_helper.unlink, self.address)
+        SocketHandlerTest.setUp(self)
+
+@support.requires_working_socket()
+@threading_helper.requires_working_threading()
+class DatagramHandlerTest(BaseTest):
+
+    """Test for DatagramHandler."""
+
+    server_class = TestUDPServer
+    address = ('localhost', 0)
+
+    def setUp(self):
+        """Set up a UDP server to receive log messages, and a DatagramHandler
+        pointing to that server's address and port."""
+        BaseTest.setUp(self)
+        # Issue #29177: deal with errors that happen during setup
+        self.server = self.sock_hdlr = self.server_exception = None
+        try:
+            self.server = server = self.server_class(self.address,
+                                                     self.handle_datagram, 0.01)
+            server.start()
+            # Uncomment next line to test error recovery in setUp()
+            # raise OSError('dummy error raised')
+        except OSError as e:
+            self.server_exception = e
+            return
+        server.ready.wait()
+        hcls = logging.handlers.DatagramHandler
+        if isinstance(server.server_address, tuple):
+            self.sock_hdlr = hcls('localhost', server.port)
+        else:
+            self.sock_hdlr = hcls(server.server_address, None)
+        self.log_output = ''
+        self.root_logger.removeHandler(self.root_logger.handlers[0])
+        self.root_logger.addHandler(self.sock_hdlr)
+        self.handled = threading.Event()
+
+    def tearDown(self):
+        """Shutdown the UDP server."""
+        try:
+            if self.server:
+                self.server.stop()
+            if self.sock_hdlr:
+                self.root_logger.removeHandler(self.sock_hdlr)
+                self.sock_hdlr.close()
+        finally:
+            BaseTest.tearDown(self)
+
+    def handle_datagram(self, request):
+        slen = struct.pack('>L', 0) # length of prefix
+        packet = request.packet[len(slen):]
+        obj = pickle.loads(packet)
+        record = logging.makeLogRecord(obj)
+        self.log_output += record.msg + '\n'
+        self.handled.set()
+
+    def test_output(self):
+        # The log message sent to the DatagramHandler is properly received.
+        if self.server_exception:
+            self.skipTest(self.server_exception)
+        logger = logging.getLogger("udp")
+        logger.error("spam")
+        self.handled.wait()
+        self.handled.clear()
+        logger.error("eggs")
+        self.handled.wait()
+        self.assertEqual(self.log_output, "spam\neggs\n")
+
+@unittest.skipUnless(hasattr(socket, "AF_UNIX"), "Unix sockets required")
+class UnixDatagramHandlerTest(DatagramHandlerTest):
+
+    """Test for DatagramHandler using Unix sockets."""
+
+    if hasattr(socket, "AF_UNIX"):
+        server_class = TestUnixDatagramServer
+
+    def setUp(self):
+        # override the definition in the base class
+        self.address = socket_helper.create_unix_domain_name()
+        self.addCleanup(os_helper.unlink, self.address)
+        DatagramHandlerTest.setUp(self)
+
+@support.requires_working_socket()
+@threading_helper.requires_working_threading()
+class SysLogHandlerTest(BaseTest):
+
+    """Test for SysLogHandler using UDP."""
+
+    server_class = TestUDPServer
+    address = ('localhost', 0)
+
+    def setUp(self):
+        """Set up a UDP server to receive log messages, and a SysLogHandler
+        pointing to that server's address and port."""
+        BaseTest.setUp(self)
+        # Issue #29177: deal with errors that happen during setup
+        self.server = self.sl_hdlr = self.server_exception = None
+        try:
+            self.server = server = self.server_class(self.address,
+                                                     self.handle_datagram, 0.01)
+            server.start()
+            # Uncomment next line to test error recovery in setUp()
+            # raise OSError('dummy error raised')
+        except OSError as e:
+            self.server_exception = e
+            return
+        server.ready.wait()
+        hcls = logging.handlers.SysLogHandler
+        if isinstance(server.server_address, tuple):
+            self.sl_hdlr = hcls((server.server_address[0], server.port))
+        else:
+            self.sl_hdlr = hcls(server.server_address)
+        self.log_output = b''
+        self.root_logger.removeHandler(self.root_logger.handlers[0])
+        self.root_logger.addHandler(self.sl_hdlr)
+        self.handled = threading.Event()
+
+    def tearDown(self):
+        """Shutdown the server."""
+        try:
+            if self.server:
+                self.server.stop()
+            if self.sl_hdlr:
+                self.root_logger.removeHandler(self.sl_hdlr)
+                self.sl_hdlr.close()
+        finally:
+            BaseTest.tearDown(self)
+
+    def handle_datagram(self, request):
+        self.log_output = request.packet
+        self.handled.set()
+
+    def test_output(self):
+        if self.server_exception:
+            self.skipTest(self.server_exception)
+        # The log message sent to the SysLogHandler is properly received.
+        logger = logging.getLogger("slh")
+        logger.error("sp\xe4m")
+        self.handled.wait(support.LONG_TIMEOUT)
+        self.assertEqual(self.log_output, b'<11>sp\xc3\xa4m\x00')
+        self.handled.clear()
+        self.sl_hdlr.append_nul = False
+        logger.error("sp\xe4m")
+        self.handled.wait(support.LONG_TIMEOUT)
+        self.assertEqual(self.log_output, b'<11>sp\xc3\xa4m')
+        self.handled.clear()
+        self.sl_hdlr.ident = "h\xe4m-"
+        logger.error("sp\xe4m")
+        self.handled.wait(support.LONG_TIMEOUT)
+        self.assertEqual(self.log_output, b'<11>h\xc3\xa4m-sp\xc3\xa4m')
+
+    def test_udp_reconnection(self):
+        logger = logging.getLogger("slh")
+        self.sl_hdlr.close()
+        self.handled.clear()
+        logger.error("sp\xe4m")
+        self.handled.wait(support.LONG_TIMEOUT)
+        self.assertEqual(self.log_output, b'<11>sp\xc3\xa4m\x00')
+
+@unittest.skipUnless(hasattr(socket, "AF_UNIX"), "Unix sockets required")
+class UnixSysLogHandlerTest(SysLogHandlerTest):
+
+    """Test for SysLogHandler with Unix sockets."""
+
+    if hasattr(socket, "AF_UNIX"):
+        server_class = TestUnixDatagramServer
+
+    def setUp(self):
+        # override the definition in the base class
+        self.address = socket_helper.create_unix_domain_name()
+        self.addCleanup(os_helper.unlink, self.address)
+        SysLogHandlerTest.setUp(self)
+
+@unittest.skipUnless(socket_helper.IPV6_ENABLED,
+                     'IPv6 support required for this test.')
+class IPv6SysLogHandlerTest(SysLogHandlerTest):
+
+    """Test for SysLogHandler with IPv6 host."""
+
+    server_class = TestUDPServer
+    address = ('::1', 0)
+
+    def setUp(self):
+        self.server_class.address_family = socket.AF_INET6
+        super(IPv6SysLogHandlerTest, self).setUp()
+
+    def tearDown(self):
+        self.server_class.address_family = socket.AF_INET
+        super(IPv6SysLogHandlerTest, self).tearDown()
+
+@support.requires_working_socket()
+@threading_helper.requires_working_threading()
+class HTTPHandlerTest(BaseTest):
+    """Test for HTTPHandler."""
+
+    def setUp(self):
+        """Set up an HTTP server to receive log messages, and a HTTPHandler
+        pointing to that server's address and port."""
+        BaseTest.setUp(self)
+        self.handled = threading.Event()
+
+    def handle_request(self, request):
+        self.command = request.command
+        self.log_data = urlparse(request.path)
+        if self.command == 'POST':
+            try:
+                rlen = int(request.headers['Content-Length'])
+                self.post_data = request.rfile.read(rlen)
+            except:
+                self.post_data = None
+        request.send_response(200)
+        request.end_headers()
+        self.handled.set()
+
+    # TODO: RUSTPYTHON
+    @unittest.skip("RUSTPYTHON")
+    def test_output(self):
+        # The log message sent to the HTTPHandler is properly received.
+        logger = logging.getLogger("http")
+        root_logger = self.root_logger
+        root_logger.removeHandler(self.root_logger.handlers[0])
+        for secure in (False, True):
+            addr = ('localhost', 0)
+            if secure:
+                try:
+                    import ssl
+                except ImportError:
+                    sslctx = None
+                else:
+                    here = os.path.dirname(__file__)
+                    localhost_cert = os.path.join(here, "certdata", "keycert.pem")
+                    sslctx = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
+                    sslctx.load_cert_chain(localhost_cert)
+
+                    context = ssl.create_default_context(cafile=localhost_cert)
+            else:
+                sslctx = None
+                context = None
+            self.server = server = TestHTTPServer(addr, self.handle_request,
+                                                  0.01, sslctx=sslctx)
+            server.start()
+            server.ready.wait()
+            host = 'localhost:%d' % server.server_port
+            secure_client = secure and sslctx
+            self.h_hdlr = logging.handlers.HTTPHandler(host, '/frob',
+                                                       secure=secure_client,
+                                                       context=context,
+                                                       credentials=('foo', 'bar'))
+            self.log_data = None
+            root_logger.addHandler(self.h_hdlr)
+
+            for method in ('GET', 'POST'):
+                self.h_hdlr.method = method
+                self.handled.clear()
+                msg = "sp\xe4m"
+                logger.error(msg)
+                self.handled.wait()
+                self.assertEqual(self.log_data.path, '/frob')
+                self.assertEqual(self.command, method)
+                if method == 'GET':
+                    d = parse_qs(self.log_data.query)
+                else:
+                    d = parse_qs(self.post_data.decode('utf-8'))
+                self.assertEqual(d['name'], ['http'])
+                self.assertEqual(d['funcName'], ['test_output'])
+                self.assertEqual(d['msg'], [msg])
+
+            self.server.stop()
+            self.root_logger.removeHandler(self.h_hdlr)
+            self.h_hdlr.close()
+
+class MemoryTest(BaseTest):
+
+    """Test memory persistence of logger objects."""
+
+    def setUp(self):
+        """Create a dict to remember potentially destroyed objects."""
+        BaseTest.setUp(self)
+        self._survivors = {}
+
+    def _watch_for_survival(self, *args):
+        """Watch the given objects for survival, by creating weakrefs to
+        them."""
+        for obj in args:
+            key = id(obj), repr(obj)
+            self._survivors[key] = weakref.ref(obj)
+
+    def _assertTruesurvival(self):
+        """Assert that all objects watched for survival have survived."""
+        # Trigger cycle breaking.
+        gc.collect()
+        dead = []
+        for (id_, repr_), ref in self._survivors.items():
+            if ref() is None:
+                dead.append(repr_)
+        if dead:
+            self.fail("%d objects should have survived "
+                      "but have been destroyed: %s" % (len(dead), ", ".join(dead)))
+
+    def test_persistent_loggers(self):
+        # Logger objects are persistent and retain their configuration, even
+        #  if visible references are destroyed.
+        self.root_logger.setLevel(logging.INFO)
+        foo = logging.getLogger("foo")
+        self._watch_for_survival(foo)
+        foo.setLevel(logging.DEBUG)
+        self.root_logger.debug(self.next_message())
+        foo.debug(self.next_message())
+        self.assert_log_lines([
+            ('foo', 'DEBUG', '2'),
+        ])
+        del foo
+        # foo has survived.
+        self._assertTruesurvival()
+        # foo has retained its settings.
+        bar = logging.getLogger("foo")
+        bar.debug(self.next_message())
+        self.assert_log_lines([
+            ('foo', 'DEBUG', '2'),
+            ('foo', 'DEBUG', '3'),
+        ])
+
+
+class EncodingTest(BaseTest):
+    def test_encoding_plain_file(self):
+        # In Python 2.x, a plain file object is treated as having no encoding.
+        log = logging.getLogger("test")
+        fn = make_temp_file(".log", "test_logging-1-")
+        # the non-ascii data we write to the log.
+        data = "foo\x80"
+        try:
+            handler = logging.FileHandler(fn, encoding="utf-8")
+            log.addHandler(handler)
+            try:
+                # write non-ascii data to the log.
+                log.warning(data)
+            finally:
+                log.removeHandler(handler)
+                handler.close()
+            # check we wrote exactly those bytes, ignoring trailing \n etc
+            f = open(fn, encoding="utf-8")
+            try:
+                self.assertEqual(f.read().rstrip(), data)
+            finally:
+                f.close()
+        finally:
+            if os.path.isfile(fn):
+                os.remove(fn)
+
+    def test_encoding_cyrillic_unicode(self):
+        log = logging.getLogger("test")
+        # Get a message in Unicode: Do svidanya in Cyrillic (meaning goodbye)
+        message = '\u0434\u043e \u0441\u0432\u0438\u0434\u0430\u043d\u0438\u044f'
+        # Ensure it's written in a Cyrillic encoding
+        writer_class = codecs.getwriter('cp1251')
+        writer_class.encoding = 'cp1251'
+        stream = io.BytesIO()
+        writer = writer_class(stream, 'strict')
+        handler = logging.StreamHandler(writer)
+        log.addHandler(handler)
+        try:
+            log.warning(message)
+        finally:
+            log.removeHandler(handler)
+            handler.close()
+        # check we wrote exactly those bytes, ignoring trailing \n etc
+        s = stream.getvalue()
+        # Compare against what the data should be when encoded in CP-1251
+        self.assertEqual(s, b'\xe4\xee \xf1\xe2\xe8\xe4\xe0\xed\xe8\xff\n')
+
+
+class WarningsTest(BaseTest):
+
+    def test_warnings(self):
+        with warnings.catch_warnings():
+            logging.captureWarnings(True)
+            self.addCleanup(logging.captureWarnings, False)
+            warnings.filterwarnings("always", category=UserWarning)
+            stream = io.StringIO()
+            h = logging.StreamHandler(stream)
+            logger = logging.getLogger("py.warnings")
+            logger.addHandler(h)
+            warnings.warn("I'm warning you...")
+            logger.removeHandler(h)
+            s = stream.getvalue()
+            h.close()
+            self.assertGreater(s.find("UserWarning: I'm warning you...\n"), 0)
+
+            # See if an explicit file uses the original implementation
+            a_file = io.StringIO()
+            warnings.showwarning("Explicit", UserWarning, "dummy.py", 42,
+                                 a_file, "Dummy line")
+            s = a_file.getvalue()
+            a_file.close()
+            self.assertEqual(s,
+                             "dummy.py:42: UserWarning: Explicit\n  Dummy line\n")
+
+    def test_warnings_no_handlers(self):
+        with warnings.catch_warnings():
+            logging.captureWarnings(True)
+            self.addCleanup(logging.captureWarnings, False)
+
+            # confirm our assumption: no loggers are set
+            logger = logging.getLogger("py.warnings")
+            self.assertEqual(logger.handlers, [])
+
+            warnings.showwarning("Explicit", UserWarning, "dummy.py", 42)
+            self.assertEqual(len(logger.handlers), 1)
+            self.assertIsInstance(logger.handlers[0], logging.NullHandler)
+
+
+def formatFunc(format, datefmt=None):
+    return logging.Formatter(format, datefmt)
+
+class myCustomFormatter:
+    def __init__(self, fmt, datefmt=None):
+        pass
+
+def handlerFunc():
+    return logging.StreamHandler()
+
+class CustomHandler(logging.StreamHandler):
+    pass
+
+class CustomListener(logging.handlers.QueueListener):
+    pass
+
+class CustomQueue(queue.Queue):
+    pass
+
+class CustomQueueProtocol:
+    def __init__(self, maxsize=0):
+        self.queue = queue.Queue(maxsize)
+
+    def __getattr__(self, attribute):
+        queue = object.__getattribute__(self, 'queue')
+        return getattr(queue, attribute)
+
+class CustomQueueFakeProtocol(CustomQueueProtocol):
+    # An object implementing the minimial Queue API for
+    # the logging module but with incorrect signatures.
+    #
+    # The object will be considered a valid queue class since we
+    # do not check the signatures (only callability of methods)
+    # but will NOT be usable in production since a TypeError will
+    # be raised due to the extra argument in 'put_nowait'.
+    def put_nowait(self):
+        pass
+
+class CustomQueueWrongProtocol(CustomQueueProtocol):
+    put_nowait = None
+
+class MinimalQueueProtocol:
+    def put_nowait(self, x): pass
+    def get(self): pass
+
+def queueMaker():
+    return queue.Queue()
+
+def listenerMaker(arg1, arg2, respect_handler_level=False):
+    def func(queue, *handlers, **kwargs):
+        kwargs.setdefault('respect_handler_level', respect_handler_level)
+        return CustomListener(queue, *handlers, **kwargs)
+    return func
+
+class ConfigDictTest(BaseTest):
+
+    """Reading logging config from a dictionary."""
+
+    check_no_resource_warning = warnings_helper.check_no_resource_warning
+    expected_log_pat = r"^(\w+) \+\+ (\w+)$"
+
+    # config0 is a standard configuration.
+    config0 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # config1 adds a little to the standard configuration.
+    config1 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config1a moves the handler to the root. Used with config8a
+    config1a = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # config2 has a subtle configuration error that should be reported
+    config2 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdbout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # As config1 but with a misspelt level on a handler
+    config2a = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NTOSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+
+    # As config1 but with a misspelt level on a logger
+    config2b = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WRANING',
+        },
+    }
+
+    # config3 has a less subtle configuration error
+    config3 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'misspelled_name',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config4 specifies a custom formatter class to be loaded
+    config4 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                '()' : __name__ + '.ExceptionFormatter',
+                'format' : '%(levelname)s:%(name)s:%(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'root' : {
+            'level' : 'NOTSET',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # As config4 but using an actual callable rather than a string
+    config4a = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                '()' : ExceptionFormatter,
+                'format' : '%(levelname)s:%(name)s:%(message)s',
+            },
+            'form2' : {
+                '()' : __name__ + '.formatFunc',
+                'format' : '%(levelname)s:%(name)s:%(message)s',
+            },
+            'form3' : {
+                '()' : formatFunc,
+                'format' : '%(levelname)s:%(name)s:%(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+            'hand2' : {
+                '()' : handlerFunc,
+            },
+        },
+        'root' : {
+            'level' : 'NOTSET',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # config5 specifies a custom handler class to be loaded
+    config5 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : __name__ + '.CustomHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config6 specifies a custom handler class to be loaded
+    # but has bad arguments
+    config6 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : __name__ + '.CustomHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+                '9' : 'invalid parameter name',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config 7 does not define compiler.parser but defines compiler.lexer
+    # so compiler.parser should be disabled after applying it
+    config7 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.lexer' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config8 defines both compiler and compiler.lexer
+    # so compiler.parser should not be disabled (since
+    # compiler is defined)
+    config8 = {
+        'version': 1,
+        'disable_existing_loggers' : False,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+            'compiler.lexer' : {
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # config8a disables existing loggers
+    config8a = {
+        'version': 1,
+        'disable_existing_loggers' : True,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+            'compiler.lexer' : {
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    config9 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'WARNING',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'WARNING',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'NOTSET',
+        },
+    }
+
+    config9a = {
+        'version': 1,
+        'incremental' : True,
+        'handlers' : {
+            'hand1' : {
+                'level' : 'WARNING',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'INFO',
+            },
+        },
+    }
+
+    config9b = {
+        'version': 1,
+        'incremental' : True,
+        'handlers' : {
+            'hand1' : {
+                'level' : 'INFO',
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'INFO',
+            },
+        },
+    }
+
+    # As config1 but with a filter added
+    config10 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'filters' : {
+            'filt1' : {
+                'name' : 'compiler.parser',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+                'filters' : ['filt1'],
+            },
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'filters' : ['filt1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # As config1 but using cfg:// references
+    config11 = {
+        'version': 1,
+        'true_formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handler_configs': {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'formatters' : 'cfg://true_formatters',
+        'handlers' : {
+            'hand1' : 'cfg://handler_configs[hand1]',
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # As config11 but missing the version key
+    config12 = {
+        'true_formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handler_configs': {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'formatters' : 'cfg://true_formatters',
+        'handlers' : {
+            'hand1' : 'cfg://handler_configs[hand1]',
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # As config11 but using an unsupported version
+    config13 = {
+        'version': 2,
+        'true_formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handler_configs': {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'formatters' : 'cfg://true_formatters',
+        'handlers' : {
+            'hand1' : 'cfg://handler_configs[hand1]',
+        },
+        'loggers' : {
+            'compiler.parser' : {
+                'level' : 'DEBUG',
+                'handlers' : ['hand1'],
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+        },
+    }
+
+    # As config0, but with properties
+    config14 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(levelname)s ++ %(message)s',
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+                '.': {
+                    'foo': 'bar',
+                    'terminator': '!\n',
+                }
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    # config0 but with default values for formatter. Skipped 15, it is defined
+    # in the test code.
+    config16 = {
+        'version': 1,
+        'formatters': {
+            'form1' : {
+                'format' : '%(message)s ++ %(customfield)s',
+                'defaults': {"customfield": "defaultvalue"}
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'form1',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    class CustomFormatter(logging.Formatter):
+        custom_property = "."
+
+        def format(self, record):
+            return super().format(record)
+
+    config17 = {
+        'version': 1,
+        'formatters': {
+            "custom": {
+                "()": CustomFormatter,
+                "style": "{",
+                "datefmt": "%Y-%m-%d %H:%M:%S",
+                "format": "{message}", # <-- to force an exception when configuring
+                ".": {
+                    "custom_property": "value"
+                }
+            }
+        },
+        'handlers' : {
+            'hand1' : {
+                'class' : 'logging.StreamHandler',
+                'formatter' : 'custom',
+                'level' : 'NOTSET',
+                'stream'  : 'ext://sys.stdout',
+            },
+        },
+        'root' : {
+            'level' : 'WARNING',
+            'handlers' : ['hand1'],
+        },
+    }
+
+    config18  = {
+        "version": 1,
+        "handlers": {
+            "console": {
+                "class": "logging.StreamHandler",
+                "level": "DEBUG",
+            },
+            "buffering": {
+                "class": "logging.handlers.MemoryHandler",
+                "capacity": 5,
+                "target": "console",
+                "level": "DEBUG",
+                "flushLevel": "ERROR"
+            }
+        },
+        "loggers": {
+            "mymodule": {
+                "level": "DEBUG",
+                "handlers": ["buffering"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    bad_format = {
+        "version": 1,
+        "formatters": {
+            "mySimpleFormatter": {
+                "format": "%(asctime)s (%(name)s) %(levelname)s: %(message)s",
+                "style": "$"
+            }
+        },
+        "handlers": {
+            "fileGlobal": {
+                "class": "logging.StreamHandler",
+                "level": "DEBUG",
+                "formatter": "mySimpleFormatter"
+            },
+            "bufferGlobal": {
+                "class": "logging.handlers.MemoryHandler",
+                "capacity": 5,
+                "formatter": "mySimpleFormatter",
+                "target": "fileGlobal",
+                "level": "DEBUG"
+            }
+        },
+        "loggers": {
+            "mymodule": {
+                "level": "DEBUG",
+                "handlers": ["bufferGlobal"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    # Configuration with custom logging.Formatter subclass as '()' key and 'validate' set to False
+    custom_formatter_class_validate = {
+        'version': 1,
+        'formatters': {
+            'form1': {
+                '()': __name__ + '.ExceptionFormatter',
+                'format': '%(levelname)s:%(name)s:%(message)s',
+                'validate': False,
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class': 'logging.StreamHandler',
+                'formatter': 'form1',
+                'level': 'NOTSET',
+                'stream': 'ext://sys.stdout',
+            },
+        },
+        "loggers": {
+            "my_test_logger_custom_formatter": {
+                "level": "DEBUG",
+                "handlers": ["hand1"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    # Configuration with custom logging.Formatter subclass as 'class' key and 'validate' set to False
+    custom_formatter_class_validate2 = {
+        'version': 1,
+        'formatters': {
+            'form1': {
+                'class': __name__ + '.ExceptionFormatter',
+                'format': '%(levelname)s:%(name)s:%(message)s',
+                'validate': False,
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class': 'logging.StreamHandler',
+                'formatter': 'form1',
+                'level': 'NOTSET',
+                'stream': 'ext://sys.stdout',
+            },
+        },
+        "loggers": {
+            "my_test_logger_custom_formatter": {
+                "level": "DEBUG",
+                "handlers": ["hand1"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    # Configuration with custom class that is not inherited from logging.Formatter
+    custom_formatter_class_validate3 = {
+        'version': 1,
+        'formatters': {
+            'form1': {
+                'class': __name__ + '.myCustomFormatter',
+                'format': '%(levelname)s:%(name)s:%(message)s',
+                'validate': False,
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class': 'logging.StreamHandler',
+                'formatter': 'form1',
+                'level': 'NOTSET',
+                'stream': 'ext://sys.stdout',
+            },
+        },
+        "loggers": {
+            "my_test_logger_custom_formatter": {
+                "level": "DEBUG",
+                "handlers": ["hand1"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    # Configuration with custom function, 'validate' set to False and no defaults
+    custom_formatter_with_function = {
+        'version': 1,
+        'formatters': {
+            'form1': {
+                '()': formatFunc,
+                'format': '%(levelname)s:%(name)s:%(message)s',
+                'validate': False,
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class': 'logging.StreamHandler',
+                'formatter': 'form1',
+                'level': 'NOTSET',
+                'stream': 'ext://sys.stdout',
+            },
+        },
+        "loggers": {
+            "my_test_logger_custom_formatter": {
+                "level": "DEBUG",
+                "handlers": ["hand1"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    # Configuration with custom function, and defaults
+    custom_formatter_with_defaults = {
+        'version': 1,
+        'formatters': {
+            'form1': {
+                '()': formatFunc,
+                'format': '%(levelname)s:%(name)s:%(message)s:%(customfield)s',
+                'defaults': {"customfield": "myvalue"}
+            },
+        },
+        'handlers' : {
+            'hand1' : {
+                'class': 'logging.StreamHandler',
+                'formatter': 'form1',
+                'level': 'NOTSET',
+                'stream': 'ext://sys.stdout',
+            },
+        },
+        "loggers": {
+            "my_test_logger_custom_formatter": {
+                "level": "DEBUG",
+                "handlers": ["hand1"],
+                "propagate": "true"
+            }
+        }
+    }
+
+    config_queue_handler = {
+        'version': 1,
+        'handlers' : {
+            'h1' : {
+                'class': 'logging.FileHandler',
+            },
+            # key is before depended on handlers to test that deferred config works
+            'ah' : {
+                'class': 'logging.handlers.QueueHandler',
+                'handlers': ['h1']
+            },
+        },
+        "root": {
+            "level": "DEBUG",
+            "handlers": ["ah"]
+        }
+    }
+
+    def apply_config(self, conf):
+        logging.config.dictConfig(conf)
+
+    def check_handler(self, name, cls):
+        h = logging.getHandlerByName(name)
+        self.assertIsInstance(h, cls)
+
+    def test_config0_ok(self):
+        # A simple config which overrides the default settings.
+        with support.captured_stdout() as output:
+            self.apply_config(self.config0)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger()
+            # Won't output anything
+            logger.info(self.next_message())
+            # Outputs a message
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config1_ok(self, config=config1):
+        # A config defining a sub-parser as well.
+        with support.captured_stdout() as output:
+            self.apply_config(config)
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config2_failure(self):
+        # A simple config which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config2)
+
+    def test_config2a_failure(self):
+        # A simple config which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config2a)
+
+    def test_config2b_failure(self):
+        # A simple config which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config2b)
+
+    def test_config3_failure(self):
+        # A simple config which overrides the default settings.
+        self.assertRaises(Exception, self.apply_config, self.config3)
+
+    def test_config4_ok(self):
+        # A config specifying a custom formatter class.
+        with support.captured_stdout() as output:
+            self.apply_config(self.config4)
+            self.check_handler('hand1', logging.StreamHandler)
+            #logger = logging.getLogger()
+            try:
+                raise RuntimeError()
+            except RuntimeError:
+                logging.exception("just testing")
+            sys.stdout.seek(0)
+            self.assertEqual(output.getvalue(),
+                             "ERROR:root:just testing\nGot a [RuntimeError]\n")
+            # Original logger output is empty
+            self.assert_log_lines([])
+
+    def test_config4a_ok(self):
+        # A config specifying a custom formatter class.
+        with support.captured_stdout() as output:
+            self.apply_config(self.config4a)
+            #logger = logging.getLogger()
+            try:
+                raise RuntimeError()
+            except RuntimeError:
+                logging.exception("just testing")
+            sys.stdout.seek(0)
+            self.assertEqual(output.getvalue(),
+                             "ERROR:root:just testing\nGot a [RuntimeError]\n")
+            # Original logger output is empty
+            self.assert_log_lines([])
+
+    def test_config5_ok(self):
+        self.test_config1_ok(config=self.config5)
+        self.check_handler('hand1', CustomHandler)
+
+    def test_config6_failure(self):
+        self.assertRaises(Exception, self.apply_config, self.config6)
+
+    def test_config7_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config1)
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+        with support.captured_stdout() as output:
+            self.apply_config(self.config7)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            self.assertTrue(logger.disabled)
+            logger = logging.getLogger("compiler.lexer")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '3'),
+                ('ERROR', '4'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    # Same as test_config_7_ok but don't disable old loggers.
+    def test_config_8_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config1)
+            logger = logging.getLogger("compiler.parser")
+            # All will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+        with support.captured_stdout() as output:
+            self.apply_config(self.config8)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            self.assertFalse(logger.disabled)
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            logger = logging.getLogger("compiler.lexer")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '3'),
+                ('ERROR', '4'),
+                ('INFO', '5'),
+                ('ERROR', '6'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config_8a_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config1a)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            # See issue #11424. compiler-hyphenated sorts
+            # between compiler and compiler.xyz and this
+            # was preventing compiler.xyz from being included
+            # in the child loggers of compiler because of an
+            # overzealous loop termination condition.
+            hyphenated = logging.getLogger('compiler-hyphenated')
+            # All will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            hyphenated.critical(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+                ('CRITICAL', '3'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+        with support.captured_stdout() as output:
+            self.apply_config(self.config8a)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            self.assertFalse(logger.disabled)
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            logger = logging.getLogger("compiler.lexer")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            # Will not appear
+            hyphenated.critical(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '4'),
+                ('ERROR', '5'),
+                ('INFO', '6'),
+                ('ERROR', '7'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    def test_config_9_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config9)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            # Nothing will be output since both handler and logger are set to WARNING
+            logger.info(self.next_message())
+            self.assert_log_lines([], stream=output)
+            self.apply_config(self.config9a)
+            # Nothing will be output since handler is still set to WARNING
+            logger.info(self.next_message())
+            self.assert_log_lines([], stream=output)
+            self.apply_config(self.config9b)
+            # Message should now be output
+            logger.info(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '3'),
+            ], stream=output)
+
+    def test_config_10_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config10)
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            logger.warning(self.next_message())
+            logger = logging.getLogger('compiler')
+            # Not output, because filtered
+            logger.warning(self.next_message())
+            logger = logging.getLogger('compiler.lexer')
+            # Not output, because filtered
+            logger.warning(self.next_message())
+            logger = logging.getLogger("compiler.parser.codegen")
+            # Output, as not filtered
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('WARNING', '1'),
+                ('ERROR', '4'),
+            ], stream=output)
+
+    def test_config11_ok(self):
+        self.test_config1_ok(self.config11)
+
+    def test_config12_failure(self):
+        self.assertRaises(Exception, self.apply_config, self.config12)
+
+    def test_config13_failure(self):
+        self.assertRaises(Exception, self.apply_config, self.config13)
+
+    def test_config14_ok(self):
+        with support.captured_stdout() as output:
+            self.apply_config(self.config14)
+            h = logging._handlers['hand1']
+            self.assertEqual(h.foo, 'bar')
+            self.assertEqual(h.terminator, '!\n')
+            logging.warning('Exclamation')
+            self.assertTrue(output.getvalue().endswith('Exclamation!\n'))
+
+    def test_config15_ok(self):
+
+        with self.check_no_resource_warning():
+            fn = make_temp_file(".log", "test_logging-X-")
+
+            config = {
+                "version": 1,
+                "handlers": {
+                    "file": {
+                        "class": "logging.FileHandler",
+                        "filename": fn,
+                        "encoding": "utf-8",
+                    }
+                },
+                "root": {
+                    "handlers": ["file"]
+                }
+            }
+
+            self.apply_config(config)
+            self.apply_config(config)
+
+        handler = logging.root.handlers[0]
+        self.addCleanup(closeFileHandler, handler, fn)
+
+    def test_config16_ok(self):
+        self.apply_config(self.config16)
+        h = logging._handlers['hand1']
+
+        # Custom value
+        result = h.formatter.format(logging.makeLogRecord(
+            {'msg': 'Hello', 'customfield': 'customvalue'}))
+        self.assertEqual(result, 'Hello ++ customvalue')
+
+        # Default value
+        result = h.formatter.format(logging.makeLogRecord(
+            {'msg': 'Hello'}))
+        self.assertEqual(result, 'Hello ++ defaultvalue')
+
+    def test_config17_ok(self):
+        self.apply_config(self.config17)
+        h = logging._handlers['hand1']
+        self.assertEqual(h.formatter.custom_property, 'value')
+
+    def test_config18_ok(self):
+        self.apply_config(self.config18)
+        handler = logging.getLogger('mymodule').handlers[0]
+        self.assertEqual(handler.flushLevel, logging.ERROR)
+
+    def setup_via_listener(self, text, verify=None):
+        text = text.encode("utf-8")
+        # Ask for a randomly assigned port (by using port 0)
+        t = logging.config.listen(0, verify)
+        t.start()
+        t.ready.wait()
+        # Now get the port allocated
+        port = t.port
+        t.ready.clear()
+        try:
+            sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            sock.settimeout(2.0)
+            sock.connect(('localhost', port))
+
+            slen = struct.pack('>L', len(text))
+            s = slen + text
+            sentsofar = 0
+            left = len(s)
+            while left > 0:
+                sent = sock.send(s[sentsofar:])
+                sentsofar += sent
+                left -= sent
+            sock.close()
+        finally:
+            t.ready.wait(2.0)
+            logging.config.stopListening()
+            threading_helper.join_thread(t)
+
+    @support.requires_working_socket()
+    def test_listen_config_10_ok(self):
+        with support.captured_stdout() as output:
+            self.setup_via_listener(json.dumps(self.config10))
+            self.check_handler('hand1', logging.StreamHandler)
+            logger = logging.getLogger("compiler.parser")
+            logger.warning(self.next_message())
+            logger = logging.getLogger('compiler')
+            # Not output, because filtered
+            logger.warning(self.next_message())
+            logger = logging.getLogger('compiler.lexer')
+            # Not output, because filtered
+            logger.warning(self.next_message())
+            logger = logging.getLogger("compiler.parser.codegen")
+            # Output, as not filtered
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('WARNING', '1'),
+                ('ERROR', '4'),
+            ], stream=output)
+
+    @support.requires_working_socket()
+    def test_listen_config_1_ok(self):
+        with support.captured_stdout() as output:
+            self.setup_via_listener(textwrap.dedent(ConfigFileTest.config1))
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+            self.assert_log_lines([
+                ('INFO', '1'),
+                ('ERROR', '2'),
+            ], stream=output)
+            # Original logger output is empty.
+            self.assert_log_lines([])
+
+    @support.requires_working_socket()
+    def test_listen_verify(self):
+
+        def verify_fail(stuff):
+            return None
+
+        def verify_reverse(stuff):
+            return stuff[::-1]
+
+        logger = logging.getLogger("compiler.parser")
+        to_send = textwrap.dedent(ConfigFileTest.config1)
+        # First, specify a verification function that will fail.
+        # We expect to see no output, since our configuration
+        # never took effect.
+        with support.captured_stdout() as output:
+            self.setup_via_listener(to_send, verify_fail)
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+        self.assert_log_lines([], stream=output)
+        # Original logger output has the stuff we logged.
+        self.assert_log_lines([
+            ('INFO', '1'),
+            ('ERROR', '2'),
+        ], pat=r"^[\w.]+ -> (\w+): (\d+)$")
+
+        # Now, perform no verification. Our configuration
+        # should take effect.
+
+        with support.captured_stdout() as output:
+            self.setup_via_listener(to_send)    # no verify callable specified
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+        self.assert_log_lines([
+            ('INFO', '3'),
+            ('ERROR', '4'),
+        ], stream=output)
+        # Original logger output still has the stuff we logged before.
+        self.assert_log_lines([
+            ('INFO', '1'),
+            ('ERROR', '2'),
+        ], pat=r"^[\w.]+ -> (\w+): (\d+)$")
+
+        # Now, perform verification which transforms the bytes.
+
+        with support.captured_stdout() as output:
+            self.setup_via_listener(to_send[::-1], verify_reverse)
+            logger = logging.getLogger("compiler.parser")
+            # Both will output a message
+            logger.info(self.next_message())
+            logger.error(self.next_message())
+        self.assert_log_lines([
+            ('INFO', '5'),
+            ('ERROR', '6'),
+        ], stream=output)
+        # Original logger output still has the stuff we logged before.
+        self.assert_log_lines([
+            ('INFO', '1'),
+            ('ERROR', '2'),
+        ], pat=r"^[\w.]+ -> (\w+): (\d+)$")
+
+    def test_bad_format(self):
+        self.assertRaises(ValueError, self.apply_config, self.bad_format)
+
+    def test_bad_format_with_dollar_style(self):
+        config = copy.deepcopy(self.bad_format)
+        config['formatters']['mySimpleFormatter']['format'] = "${asctime} (${name}) ${levelname}: ${message}"
+
+        self.apply_config(config)
+        handler = logging.getLogger('mymodule').handlers[0]
+        self.assertIsInstance(handler.target, logging.Handler)
+        self.assertIsInstance(handler.formatter._style,
+                              logging.StringTemplateStyle)
+        self.assertEqual(sorted(logging.getHandlerNames()),
+                         ['bufferGlobal', 'fileGlobal'])
+
+    def test_custom_formatter_class_with_validate(self):
+        self.apply_config(self.custom_formatter_class_validate)
+        handler = logging.getLogger("my_test_logger_custom_formatter").handlers[0]
+        self.assertIsInstance(handler.formatter, ExceptionFormatter)
+
+    def test_custom_formatter_class_with_validate2(self):
+        self.apply_config(self.custom_formatter_class_validate2)
+        handler = logging.getLogger("my_test_logger_custom_formatter").handlers[0]
+        self.assertIsInstance(handler.formatter, ExceptionFormatter)
+
+    def test_custom_formatter_class_with_validate2_with_wrong_fmt(self):
+        config = self.custom_formatter_class_validate.copy()
+        config['formatters']['form1']['style'] = "$"
+
+        # Exception should not be raised as we have configured 'validate' to False
+        self.apply_config(config)
+        handler = logging.getLogger("my_test_logger_custom_formatter").handlers[0]
+        self.assertIsInstance(handler.formatter, ExceptionFormatter)
+
+    def test_custom_formatter_class_with_validate3(self):
+        self.assertRaises(ValueError, self.apply_config, self.custom_formatter_class_validate3)
+
+    def test_custom_formatter_function_with_validate(self):
+        self.assertRaises(ValueError, self.apply_config, self.custom_formatter_with_function)
+
+    def test_custom_formatter_function_with_defaults(self):
+        self.assertRaises(ValueError, self.apply_config, self.custom_formatter_with_defaults)
+
+    def test_baseconfig(self):
+        d = {
+            'atuple': (1, 2, 3),
+            'alist': ['a', 'b', 'c'],
+            'adict': {'d': 'e', 'f': 3 },
+            'nest1': ('g', ('h', 'i'), 'j'),
+            'nest2': ['k', ['l', 'm'], 'n'],
+            'nest3': ['o', 'cfg://alist', 'p'],
+        }
+        bc = logging.config.BaseConfigurator(d)
+        self.assertEqual(bc.convert('cfg://atuple[1]'), 2)
+        self.assertEqual(bc.convert('cfg://alist[1]'), 'b')
+        self.assertEqual(bc.convert('cfg://nest1[1][0]'), 'h')
+        self.assertEqual(bc.convert('cfg://nest2[1][1]'), 'm')
+        self.assertEqual(bc.convert('cfg://adict.d'), 'e')
+        self.assertEqual(bc.convert('cfg://adict[f]'), 3)
+        v = bc.convert('cfg://nest3')
+        self.assertEqual(v.pop(1), ['a', 'b', 'c'])
+        self.assertRaises(KeyError, bc.convert, 'cfg://nosuch')
+        self.assertRaises(ValueError, bc.convert, 'cfg://!')
+        self.assertRaises(KeyError, bc.convert, 'cfg://adict[2]')
+
+    def test_namedtuple(self):
+        # see bpo-39142
+        from collections import namedtuple
+
+        class MyHandler(logging.StreamHandler):
+            def __init__(self, resource, *args, **kwargs):
+                super().__init__(*args, **kwargs)
+                self.resource: namedtuple = resource
+
+            def emit(self, record):
+                record.msg += f' {self.resource.type}'
+                return super().emit(record)
+
+        Resource = namedtuple('Resource', ['type', 'labels'])
+        resource = Resource(type='my_type', labels=['a'])
+
+        config = {
+            'version': 1,
+            'handlers': {
+                'myhandler': {
+                    '()': MyHandler,
+                    'resource': resource
+                }
+            },
+            'root':  {'level': 'INFO', 'handlers': ['myhandler']},
+        }
+        with support.captured_stderr() as stderr:
+            self.apply_config(config)
+            logging.info('some log')
+        self.assertEqual(stderr.getvalue(), 'some log my_type\n')
+
+    def test_config_callable_filter_works(self):
+        def filter_(_):
+            return 1
+        self.apply_config({
+            "version": 1, "root": {"level": "DEBUG", "filters": [filter_]}
+        })
+        assert logging.getLogger().filters[0] is filter_
+        logging.getLogger().filters = []
+
+    def test_config_filter_works(self):
+        filter_ = logging.Filter("spam.eggs")
+        self.apply_config({
+            "version": 1, "root": {"level": "DEBUG", "filters": [filter_]}
+        })
+        assert logging.getLogger().filters[0] is filter_
+        logging.getLogger().filters = []
+
+    def test_config_filter_method_works(self):
+        class FakeFilter:
+            def filter(self, _):
+                return 1
+        filter_ = FakeFilter()
+        self.apply_config({
+            "version": 1, "root": {"level": "DEBUG", "filters": [filter_]}
+        })
+        assert logging.getLogger().filters[0] is filter_
+        logging.getLogger().filters = []
+
+    def test_invalid_type_raises(self):
+        class NotAFilter: pass
+        for filter_ in [None, 1, NotAFilter()]:
+            self.assertRaises(
+                ValueError,
+                self.apply_config,
+                {"version": 1, "root": {"level": "DEBUG", "filters": [filter_]}}
+            )
+
+    def do_queuehandler_configuration(self, qspec, lspec):
+        cd = copy.deepcopy(self.config_queue_handler)
+        fn = make_temp_file('.log', 'test_logging-cqh-')
+        cd['handlers']['h1']['filename'] = fn
+        if qspec is not None:
+            cd['handlers']['ah']['queue'] = qspec
+        if lspec is not None:
+            cd['handlers']['ah']['listener'] = lspec
+        qh = None
+        try:
+            self.apply_config(cd)
+            qh = logging.getHandlerByName('ah')
+            self.assertEqual(sorted(logging.getHandlerNames()), ['ah', 'h1'])
+            self.assertIsNotNone(qh.listener)
+            qh.listener.start()
+            logging.debug('foo')
+            logging.info('bar')
+            logging.warning('baz')
+
+            # Need to let the listener thread finish its work
+            while support.sleeping_retry(support.LONG_TIMEOUT,
+                                         "queue not empty"):
+                if qh.listener.queue.empty():
+                    break
+
+            # wait until the handler completed its last task
+            qh.listener.queue.join()
+
+            with open(fn, encoding='utf-8') as f:
+                data = f.read().splitlines()
+            self.assertEqual(data, ['foo', 'bar', 'baz'])
+        finally:
+            if qh:
+                qh.listener.stop()
+            h = logging.getHandlerByName('h1')
+            if h:
+                self.addCleanup(closeFileHandler, h, fn)
+            else:
+                self.addCleanup(os.remove, fn)
+
+    @threading_helper.requires_working_threading()
+    @support.requires_subprocess()
+    def test_config_queue_handler(self):
+        qs = [CustomQueue(), CustomQueueProtocol()]
+        dqs = [{'()': f'{__name__}.{cls}', 'maxsize': 10}
+               for cls in ['CustomQueue', 'CustomQueueProtocol']]
+        dl = {
+            '()': __name__ + '.listenerMaker',
+            'arg1': None,
+            'arg2': None,
+            'respect_handler_level': True
+        }
+        qvalues = (None, __name__ + '.queueMaker', __name__ + '.CustomQueue', *dqs, *qs)
+        lvalues = (None, __name__ + '.CustomListener', dl, CustomListener)
+        for qspec, lspec in itertools.product(qvalues, lvalues):
+            self.do_queuehandler_configuration(qspec, lspec)
+
+        # Some failure cases
+        qvalues = (None, 4, int, '', 'foo')
+        lvalues = (None, 4, int, '', 'bar')
+        for qspec, lspec in itertools.product(qvalues, lvalues):
+            if lspec is None and qspec is None:
+                continue
+            with self.assertRaises(ValueError) as ctx:
+                self.do_queuehandler_configuration(qspec, lspec)
+            msg = str(ctx.exception)
+            self.assertEqual(msg, "Unable to configure handler 'ah'")
+
+    def _apply_simple_queue_listener_configuration(self, qspec):
+        self.apply_config({
+            "version": 1,
+            "handlers": {
+                "queue_listener": {
+                    "class": "logging.handlers.QueueHandler",
+                    "queue": qspec,
+                },
+            },
+        })
+
+    @threading_helper.requires_working_threading()
+    @support.requires_subprocess()
+    @patch("multiprocessing.Manager")
+    def test_config_queue_handler_does_not_create_multiprocessing_manager(self, manager):
+        # gh-120868, gh-121723, gh-124653
+
+        for qspec in [
+            {"()": "queue.Queue", "maxsize": -1},
+            queue.Queue(),
+            # queue.SimpleQueue does not inherit from queue.Queue
+            queue.SimpleQueue(),
+            # CustomQueueFakeProtocol passes the checks but will not be usable
+            # since the signatures are incompatible. Checking the Queue API
+            # without testing the type of the actual queue is a trade-off
+            # between usability and the work we need to do in order to safely
+            # check that the queue object correctly implements the API.
+            CustomQueueFakeProtocol(),
+            MinimalQueueProtocol(),
+        ]:
+            with self.subTest(qspec=qspec):
+                self._apply_simple_queue_listener_configuration(qspec)
+                manager.assert_not_called()
+
+    @patch("multiprocessing.Manager")
+    def test_config_queue_handler_invalid_config_does_not_create_multiprocessing_manager(self, manager):
+        # gh-120868, gh-121723
+
+        for qspec in [object(), CustomQueueWrongProtocol()]:
+            with self.subTest(qspec=qspec), self.assertRaises(ValueError):
+                self._apply_simple_queue_listener_configuration(qspec)
+                manager.assert_not_called()
+
+    @skip_if_tsan_fork
+    @support.requires_subprocess()
+    @unittest.skipUnless(support.Py_DEBUG, "requires a debug build for testing"
+                                           " assertions in multiprocessing")
+    def test_config_reject_simple_queue_handler_multiprocessing_context(self):
+        # multiprocessing.SimpleQueue does not implement 'put_nowait'
+        # and thus cannot be used as a queue-like object (gh-124653)
+
+        import multiprocessing
+
+        if support.MS_WINDOWS:
+            start_methods = ['spawn']
+        else:
+            start_methods = ['spawn', 'fork', 'forkserver']
+
+        for start_method in start_methods:
+            with self.subTest(start_method=start_method):
+                ctx = multiprocessing.get_context(start_method)
+                qspec = ctx.SimpleQueue()
+                with self.assertRaises(ValueError):
+                    self._apply_simple_queue_listener_configuration(qspec)
+
+    @skip_if_tsan_fork
+    @support.requires_subprocess()
+    @unittest.skipUnless(support.Py_DEBUG, "requires a debug build for testing"
+                                           "assertions in multiprocessing")
+    def test_config_queue_handler_multiprocessing_context(self):
+        # regression test for gh-121723
+        if support.MS_WINDOWS:
+            start_methods = ['spawn']
+        else:
+            start_methods = ['spawn', 'fork', 'forkserver']
+        for start_method in start_methods:
+            with self.subTest(start_method=start_method):
+                ctx = multiprocessing.get_context(start_method)
+                with ctx.Manager() as manager:
+                    q = manager.Queue()
+                    records = []
+                    # use 1 process and 1 task per child to put 1 record
+                    with ctx.Pool(1, initializer=self._mpinit_issue121723,
+                                  initargs=(q, "text"), maxtasksperchild=1):
+                        records.append(q.get(timeout=60))
+                    self.assertTrue(q.empty())
+                self.assertEqual(len(records), 1)
+
+    @staticmethod
+    def _mpinit_issue121723(qspec, message_to_log):
+        # static method for pickling support
+        logging.config.dictConfig({
+            'version': 1,
+            'disable_existing_loggers': True,
+            'handlers': {
+                'log_to_parent': {
+                    'class': 'logging.handlers.QueueHandler',
+                    'queue': qspec
+                }
+            },
+            'root': {'handlers': ['log_to_parent'], 'level': 'DEBUG'}
+        })
+        # log a message (this creates a record put in the queue)
+        logging.getLogger().info(message_to_log)
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    @support.requires_subprocess()
+    def test_multiprocessing_queues(self):
+        # See gh-119819
+
+        cd = copy.deepcopy(self.config_queue_handler)
+        from multiprocessing import Queue as MQ, Manager as MM
+        q1 = MQ()  # this can't be pickled
+        q2 = MM().Queue()  # a proxy queue for use when pickling is needed
+        q3 = MM().JoinableQueue()  # a joinable proxy queue
+        for qspec in (q1, q2, q3):
+            fn = make_temp_file('.log', 'test_logging-cmpqh-')
+            cd['handlers']['h1']['filename'] = fn
+            cd['handlers']['ah']['queue'] = qspec
+            qh = None
+            try:
+                self.apply_config(cd)
+                qh = logging.getHandlerByName('ah')
+                self.assertEqual(sorted(logging.getHandlerNames()), ['ah', 'h1'])
+                self.assertIsNotNone(qh.listener)
+                self.assertIs(qh.queue, qspec)
+                self.assertIs(qh.listener.queue, qspec)
+            finally:
+                h = logging.getHandlerByName('h1')
+                if h:
+                    self.addCleanup(closeFileHandler, h, fn)
+                else:
+                    self.addCleanup(os.remove, fn)
+
+    def test_90195(self):
+        # See gh-90195
+        config = {
+            'version': 1,
+            'disable_existing_loggers': False,
+            'handlers': {
+                'console': {
+                    'level': 'DEBUG',
+                    'class': 'logging.StreamHandler',
+                },
+            },
+            'loggers': {
+                'a': {
+                    'level': 'DEBUG',
+                    'handlers': ['console']
+                }
+            }
+        }
+        logger = logging.getLogger('a')
+        self.assertFalse(logger.disabled)
+        self.apply_config(config)
+        self.assertFalse(logger.disabled)
+        # Should disable all loggers ...
+        self.apply_config({'version': 1})
+        self.assertTrue(logger.disabled)
+        del config['disable_existing_loggers']
+        self.apply_config(config)
+        # Logger should be enabled, since explicitly mentioned
+        self.assertFalse(logger.disabled)
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_111615(self):
+        # See gh-111615
+        import_helper.import_module('_multiprocessing')  # see gh-113692
+        mp = import_helper.import_module('multiprocessing')
+
+        config = {
+            'version': 1,
+            'handlers': {
+                'sink': {
+                    'class': 'logging.handlers.QueueHandler',
+                    'queue': mp.get_context('spawn').Queue(),
+                },
+            },
+            'root': {
+                'handlers': ['sink'],
+                'level': 'DEBUG',
+            },
+        }
+        logging.config.dictConfig(config)
+
+    # gh-118868: check if kwargs are passed to logging QueueHandler
+    def test_kwargs_passing(self):
+        class CustomQueueHandler(logging.handlers.QueueHandler):
+            def __init__(self, *args, **kwargs):
+                super().__init__(queue.Queue())
+                self.custom_kwargs = kwargs
+
+        custom_kwargs = {'foo': 'bar'}
+
+        config = {
+            'version': 1,
+            'handlers': {
+                'custom': {
+                    'class': CustomQueueHandler,
+                    **custom_kwargs
+                },
+            },
+            'root': {
+                'level': 'DEBUG',
+                'handlers': ['custom']
+            }
+        }
+
+        logging.config.dictConfig(config)
+
+        handler = logging.getHandlerByName('custom')
+        self.assertEqual(handler.custom_kwargs, custom_kwargs)
+
+
+class ManagerTest(BaseTest):
+    def test_manager_loggerclass(self):
+        logged = []
+
+        class MyLogger(logging.Logger):
+            def _log(self, level, msg, args, exc_info=None, extra=None):
+                logged.append(msg)
+
+        man = logging.Manager(None)
+        self.assertRaises(TypeError, man.setLoggerClass, int)
+        man.setLoggerClass(MyLogger)
+        logger = man.getLogger('test')
+        logger.warning('should appear in logged')
+        logging.warning('should not appear in logged')
+
+        self.assertEqual(logged, ['should appear in logged'])
+
+    def test_set_log_record_factory(self):
+        man = logging.Manager(None)
+        expected = object()
+        man.setLogRecordFactory(expected)
+        self.assertEqual(man.logRecordFactory, expected)
+
+class ChildLoggerTest(BaseTest):
+    def test_child_loggers(self):
+        r = logging.getLogger()
+        l1 = logging.getLogger('abc')
+        l2 = logging.getLogger('def.ghi')
+        c1 = r.getChild('xyz')
+        c2 = r.getChild('uvw.xyz')
+        self.assertIs(c1, logging.getLogger('xyz'))
+        self.assertIs(c2, logging.getLogger('uvw.xyz'))
+        c1 = l1.getChild('def')
+        c2 = c1.getChild('ghi')
+        c3 = l1.getChild('def.ghi')
+        self.assertIs(c1, logging.getLogger('abc.def'))
+        self.assertIs(c2, logging.getLogger('abc.def.ghi'))
+        self.assertIs(c2, c3)
+
+    def test_get_children(self):
+        r = logging.getLogger()
+        l1 = logging.getLogger('foo')
+        l2 = logging.getLogger('foo.bar')
+        l3 = logging.getLogger('foo.bar.baz.bozz')
+        l4 = logging.getLogger('bar')
+        kids = r.getChildren()
+        expected = {l1, l4}
+        self.assertEqual(expected, kids & expected)  # might be other kids for root
+        self.assertNotIn(l2, expected)
+        kids = l1.getChildren()
+        self.assertEqual({l2}, kids)
+        kids = l2.getChildren()
+        self.assertEqual(set(), kids)
+
+class DerivedLogRecord(logging.LogRecord):
+    pass
+
+class LogRecordFactoryTest(BaseTest):
+
+    def setUp(self):
+        class CheckingFilter(logging.Filter):
+            def __init__(self, cls):
+                self.cls = cls
+
+            def filter(self, record):
+                t = type(record)
+                if t is not self.cls:
+                    msg = 'Unexpected LogRecord type %s, expected %s' % (t,
+                                                                         self.cls)
+                    raise TypeError(msg)
+                return True
+
+        BaseTest.setUp(self)
+        self.filter = CheckingFilter(DerivedLogRecord)
+        self.root_logger.addFilter(self.filter)
+        self.orig_factory = logging.getLogRecordFactory()
+
+    def tearDown(self):
+        self.root_logger.removeFilter(self.filter)
+        BaseTest.tearDown(self)
+        logging.setLogRecordFactory(self.orig_factory)
+
+    def test_logrecord_class(self):
+        self.assertRaises(TypeError, self.root_logger.warning,
+                          self.next_message())
+        logging.setLogRecordFactory(DerivedLogRecord)
+        self.root_logger.error(self.next_message())
+        self.assert_log_lines([
+            ('root', 'ERROR', '2'),
+        ])
+
+
+@threading_helper.requires_working_threading()
+class QueueHandlerTest(BaseTest):
+    # Do not bother with a logger name group.
+    expected_log_pat = r"^[\w.]+ -> (\w+): (\d+)$"
+
+    def setUp(self):
+        BaseTest.setUp(self)
+        self.queue = queue.Queue(-1)
+        self.que_hdlr = logging.handlers.QueueHandler(self.queue)
+        self.name = 'que'
+        self.que_logger = logging.getLogger('que')
+        self.que_logger.propagate = False
+        self.que_logger.setLevel(logging.WARNING)
+        self.que_logger.addHandler(self.que_hdlr)
+
+    def tearDown(self):
+        self.que_hdlr.close()
+        BaseTest.tearDown(self)
+
+    def test_queue_handler(self):
+        self.que_logger.debug(self.next_message())
+        self.assertRaises(queue.Empty, self.queue.get_nowait)
+        self.que_logger.info(self.next_message())
+        self.assertRaises(queue.Empty, self.queue.get_nowait)
+        msg = self.next_message()
+        self.que_logger.warning(msg)
+        data = self.queue.get_nowait()
+        self.assertTrue(isinstance(data, logging.LogRecord))
+        self.assertEqual(data.name, self.que_logger.name)
+        self.assertEqual((data.msg, data.args), (msg, None))
+
+    def test_formatting(self):
+        msg = self.next_message()
+        levelname = logging.getLevelName(logging.WARNING)
+        log_format_str = '{name} -> {levelname}: {message}'
+        formatted_msg = log_format_str.format(name=self.name,
+                                              levelname=levelname, message=msg)
+        formatter = logging.Formatter(self.log_format)
+        self.que_hdlr.setFormatter(formatter)
+        self.que_logger.warning(msg)
+        log_record = self.queue.get_nowait()
+        self.assertEqual(formatted_msg, log_record.msg)
+        self.assertEqual(formatted_msg, log_record.message)
+
+    @unittest.skipUnless(hasattr(logging.handlers, 'QueueListener'),
+                         'logging.handlers.QueueListener required for this test')
+    def test_queue_listener(self):
+        handler = TestHandler(support.Matcher())
+        listener = logging.handlers.QueueListener(self.queue, handler)
+        listener.start()
+        try:
+            self.que_logger.warning(self.next_message())
+            self.que_logger.error(self.next_message())
+            self.que_logger.critical(self.next_message())
+        finally:
+            listener.stop()
+        self.assertTrue(handler.matches(levelno=logging.WARNING, message='1'))
+        self.assertTrue(handler.matches(levelno=logging.ERROR, message='2'))
+        self.assertTrue(handler.matches(levelno=logging.CRITICAL, message='3'))
+        handler.close()
+
+        # Now test with respect_handler_level set
+
+        handler = TestHandler(support.Matcher())
+        handler.setLevel(logging.CRITICAL)
+        listener = logging.handlers.QueueListener(self.queue, handler,
+                                                  respect_handler_level=True)
+        listener.start()
+        try:
+            self.que_logger.warning(self.next_message())
+            self.que_logger.error(self.next_message())
+            self.que_logger.critical(self.next_message())
+        finally:
+            listener.stop()
+        self.assertFalse(handler.matches(levelno=logging.WARNING, message='4'))
+        self.assertFalse(handler.matches(levelno=logging.ERROR, message='5'))
+        self.assertTrue(handler.matches(levelno=logging.CRITICAL, message='6'))
+        handler.close()
+
+    @unittest.skipUnless(hasattr(logging.handlers, 'QueueListener'),
+                         'logging.handlers.QueueListener required for this test')
+    def test_queue_listener_with_StreamHandler(self):
+        # Test that traceback and stack-info only appends once (bpo-34334, bpo-46755).
+        listener = logging.handlers.QueueListener(self.queue, self.root_hdlr)
+        listener.start()
+        try:
+            1 / 0
+        except ZeroDivisionError as e:
+            exc = e
+            self.que_logger.exception(self.next_message(), exc_info=exc)
+        self.que_logger.error(self.next_message(), stack_info=True)
+        listener.stop()
+        self.assertEqual(self.stream.getvalue().strip().count('Traceback'), 1)
+        self.assertEqual(self.stream.getvalue().strip().count('Stack'), 1)
+
+    @unittest.skipUnless(hasattr(logging.handlers, 'QueueListener'),
+                         'logging.handlers.QueueListener required for this test')
+    def test_queue_listener_with_multiple_handlers(self):
+        # Test that queue handler format doesn't affect other handler formats (bpo-35726).
+        self.que_hdlr.setFormatter(self.root_formatter)
+        self.que_logger.addHandler(self.root_hdlr)
+
+        listener = logging.handlers.QueueListener(self.queue, self.que_hdlr)
+        listener.start()
+        self.que_logger.error("error")
+        listener.stop()
+        self.assertEqual(self.stream.getvalue().strip(), "que -> ERROR: error")
+
+if hasattr(logging.handlers, 'QueueListener'):
+    import multiprocessing
+    from unittest.mock import patch
+
+    @threading_helper.requires_working_threading()
+    class QueueListenerTest(BaseTest):
+        """
+        Tests based on patch submitted for issue #27930. Ensure that
+        QueueListener handles all log messages.
+        """
+
+        repeat = 20
+
+        @staticmethod
+        def setup_and_log(log_queue, ident):
+            """
+            Creates a logger with a QueueHandler that logs to a queue read by a
+            QueueListener. Starts the listener, logs five messages, and stops
+            the listener.
+            """
+            logger = logging.getLogger('test_logger_with_id_%s' % ident)
+            logger.setLevel(logging.DEBUG)
+            handler = logging.handlers.QueueHandler(log_queue)
+            logger.addHandler(handler)
+            listener = logging.handlers.QueueListener(log_queue)
+            listener.start()
+
+            logger.info('one')
+            logger.info('two')
+            logger.info('three')
+            logger.info('four')
+            logger.info('five')
+
+            listener.stop()
+            logger.removeHandler(handler)
+            handler.close()
+
+        @patch.object(logging.handlers.QueueListener, 'handle')
+        def test_handle_called_with_queue_queue(self, mock_handle):
+            for i in range(self.repeat):
+                log_queue = queue.Queue()
+                self.setup_and_log(log_queue, '%s_%s' % (self.id(), i))
+            self.assertEqual(mock_handle.call_count, 5 * self.repeat,
+                             'correct number of handled log messages')
+
+        @patch.object(logging.handlers.QueueListener, 'handle')
+        def test_handle_called_with_mp_queue(self, mock_handle):
+            # bpo-28668: The multiprocessing (mp) module is not functional
+            # when the mp.synchronize module cannot be imported.
+            support.skip_if_broken_multiprocessing_synchronize()
+            for i in range(self.repeat):
+                log_queue = multiprocessing.Queue()
+                self.setup_and_log(log_queue, '%s_%s' % (self.id(), i))
+                log_queue.close()
+                log_queue.join_thread()
+            self.assertEqual(mock_handle.call_count, 5 * self.repeat,
+                             'correct number of handled log messages')
+
+        @staticmethod
+        def get_all_from_queue(log_queue):
+            try:
+                while True:
+                    yield log_queue.get_nowait()
+            except queue.Empty:
+                return []
+
+        def test_no_messages_in_queue_after_stop(self):
+            """
+            Five messages are logged then the QueueListener is stopped. This
+            test then gets everything off the queue. Failure of this test
+            indicates that messages were not registered on the queue until
+            _after_ the QueueListener stopped.
+            """
+            # bpo-28668: The multiprocessing (mp) module is not functional
+            # when the mp.synchronize module cannot be imported.
+            support.skip_if_broken_multiprocessing_synchronize()
+            for i in range(self.repeat):
+                queue = multiprocessing.Queue()
+                self.setup_and_log(queue, '%s_%s' %(self.id(), i))
+                # time.sleep(1)
+                items = list(self.get_all_from_queue(queue))
+                queue.close()
+                queue.join_thread()
+
+                expected = [[], [logging.handlers.QueueListener._sentinel]]
+                self.assertIn(items, expected,
+                              'Found unexpected messages in queue: %s' % (
+                                  [m.msg if isinstance(m, logging.LogRecord)
+                                   else m for m in items]))
+
+        def test_calls_task_done_after_stop(self):
+            # Issue 36813: Make sure queue.join does not deadlock.
+            log_queue = queue.Queue()
+            listener = logging.handlers.QueueListener(log_queue)
+            listener.start()
+            listener.stop()
+            with self.assertRaises(ValueError):
+                # Make sure all tasks are done and .join won't block.
+                log_queue.task_done()
+
+
+ZERO = datetime.timedelta(0)
+
+class UTC(datetime.tzinfo):
+    def utcoffset(self, dt):
+        return ZERO
+
+    dst = utcoffset
+
+    def tzname(self, dt):
+        return 'UTC'
+
+utc = UTC()
+
+class AssertErrorMessage:
+
+    def assert_error_message(self, exception, message, *args, **kwargs):
+        try:
+            self.assertRaises((), *args, **kwargs)
+        except exception as e:
+            self.assertEqual(message, str(e))
+
+class FormatterTest(unittest.TestCase, AssertErrorMessage):
+    def setUp(self):
+        self.common = {
+            'name': 'formatter.test',
+            'level': logging.DEBUG,
+            'pathname': os.path.join('path', 'to', 'dummy.ext'),
+            'lineno': 42,
+            'exc_info': None,
+            'func': None,
+            'msg': 'Message with %d %s',
+            'args': (2, 'placeholders'),
+        }
+        self.variants = {
+            'custom': {
+                'custom': 1234
+            }
+        }
+
+    def get_record(self, name=None):
+        result = dict(self.common)
+        if name is not None:
+            result.update(self.variants[name])
+        return logging.makeLogRecord(result)
+
+    def test_percent(self):
+        # Test %-formatting
+        r = self.get_record()
+        f = logging.Formatter('${%(message)s}')
+        self.assertEqual(f.format(r), '${Message with 2 placeholders}')
+        f = logging.Formatter('%(random)s')
+        self.assertRaises(ValueError, f.format, r)
+        self.assertFalse(f.usesTime())
+        f = logging.Formatter('%(asctime)s')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('%(asctime)-15s')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('%(asctime)#15s')
+        self.assertTrue(f.usesTime())
+
+    def test_braces(self):
+        # Test {}-formatting
+        r = self.get_record()
+        f = logging.Formatter('$%{message}%$', style='{')
+        self.assertEqual(f.format(r), '$%Message with 2 placeholders%$')
+        f = logging.Formatter('{random}', style='{')
+        self.assertRaises(ValueError, f.format, r)
+        f = logging.Formatter("{message}", style='{')
+        self.assertFalse(f.usesTime())
+        f = logging.Formatter('{asctime}', style='{')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('{asctime!s:15}', style='{')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('{asctime:15}', style='{')
+        self.assertTrue(f.usesTime())
+
+    def test_dollars(self):
+        # Test $-formatting
+        r = self.get_record()
+        f = logging.Formatter('${message}', style='$')
+        self.assertEqual(f.format(r), 'Message with 2 placeholders')
+        f = logging.Formatter('$message', style='$')
+        self.assertEqual(f.format(r), 'Message with 2 placeholders')
+        f = logging.Formatter('$$%${message}%$$', style='$')
+        self.assertEqual(f.format(r), '$%Message with 2 placeholders%$')
+        f = logging.Formatter('${random}', style='$')
+        self.assertRaises(ValueError, f.format, r)
+        self.assertFalse(f.usesTime())
+        f = logging.Formatter('${asctime}', style='$')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('$asctime', style='$')
+        self.assertTrue(f.usesTime())
+        f = logging.Formatter('${message}', style='$')
+        self.assertFalse(f.usesTime())
+        f = logging.Formatter('${asctime}--', style='$')
+        self.assertTrue(f.usesTime())
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_format_validate(self):
+        # Check correct formatting
+        # Percentage style
+        f = logging.Formatter("%(levelname)-15s - %(message) 5s - %(process)03d - %(module) - %(asctime)*.3s")
+        self.assertEqual(f._fmt, "%(levelname)-15s - %(message) 5s - %(process)03d - %(module) - %(asctime)*.3s")
+        f = logging.Formatter("%(asctime)*s - %(asctime)*.3s - %(process)-34.33o")
+        self.assertEqual(f._fmt, "%(asctime)*s - %(asctime)*.3s - %(process)-34.33o")
+        f = logging.Formatter("%(process)#+027.23X")
+        self.assertEqual(f._fmt, "%(process)#+027.23X")
+        f = logging.Formatter("%(foo)#.*g")
+        self.assertEqual(f._fmt, "%(foo)#.*g")
+
+        # StrFormat Style
+        f = logging.Formatter("$%{message}%$ - {asctime!a:15} - {customfield['key']}", style="{")
+        self.assertEqual(f._fmt, "$%{message}%$ - {asctime!a:15} - {customfield['key']}")
+        f = logging.Formatter("{process:.2f} - {custom.f:.4f}", style="{")
+        self.assertEqual(f._fmt, "{process:.2f} - {custom.f:.4f}")
+        f = logging.Formatter("{customfield!s:#<30}", style="{")
+        self.assertEqual(f._fmt, "{customfield!s:#<30}")
+        f = logging.Formatter("{message!r}", style="{")
+        self.assertEqual(f._fmt, "{message!r}")
+        f = logging.Formatter("{message!s}", style="{")
+        self.assertEqual(f._fmt, "{message!s}")
+        f = logging.Formatter("{message!a}", style="{")
+        self.assertEqual(f._fmt, "{message!a}")
+        f = logging.Formatter("{process!r:4.2}", style="{")
+        self.assertEqual(f._fmt, "{process!r:4.2}")
+        f = logging.Formatter("{process!s:<#30,.12f}- {custom:=+#30,.1d} - {module:^30}", style="{")
+        self.assertEqual(f._fmt, "{process!s:<#30,.12f}- {custom:=+#30,.1d} - {module:^30}")
+        f = logging.Formatter("{process!s:{w},.{p}}", style="{")
+        self.assertEqual(f._fmt, "{process!s:{w},.{p}}")
+        f = logging.Formatter("{foo:12.{p}}", style="{")
+        self.assertEqual(f._fmt, "{foo:12.{p}}")
+        f = logging.Formatter("{foo:{w}.6}", style="{")
+        self.assertEqual(f._fmt, "{foo:{w}.6}")
+        f = logging.Formatter("{foo[0].bar[1].baz}", style="{")
+        self.assertEqual(f._fmt, "{foo[0].bar[1].baz}")
+        f = logging.Formatter("{foo[k1].bar[k2].baz}", style="{")
+        self.assertEqual(f._fmt, "{foo[k1].bar[k2].baz}")
+        f = logging.Formatter("{12[k1].bar[k2].baz}", style="{")
+        self.assertEqual(f._fmt, "{12[k1].bar[k2].baz}")
+
+        # Dollar style
+        f = logging.Formatter("${asctime} - $message", style="$")
+        self.assertEqual(f._fmt, "${asctime} - $message")
+        f = logging.Formatter("$bar $$", style="$")
+        self.assertEqual(f._fmt, "$bar $$")
+        f = logging.Formatter("$bar $$$$", style="$")
+        self.assertEqual(f._fmt, "$bar $$$$")  # this would print two $($$)
+
+        # Testing when ValueError being raised from incorrect format
+        # Percentage Style
+        self.assertRaises(ValueError, logging.Formatter, "%(asctime)Z")
+        self.assertRaises(ValueError, logging.Formatter, "%(asctime)b")
+        self.assertRaises(ValueError, logging.Formatter, "%(asctime)*")
+        self.assertRaises(ValueError, logging.Formatter, "%(asctime)*3s")
+        self.assertRaises(ValueError, logging.Formatter, "%(asctime)_")
+        self.assertRaises(ValueError, logging.Formatter, '{asctime}')
+        self.assertRaises(ValueError, logging.Formatter, '${message}')
+        self.assertRaises(ValueError, logging.Formatter, '%(foo)#12.3*f')  # with both * and decimal number as precision
+        self.assertRaises(ValueError, logging.Formatter, '%(foo)0*.8*f')
+
+        # StrFormat Style
+        # Testing failure for '-' in field name
+        self.assert_error_message(
+            ValueError,
+            "invalid format: invalid field name/expression: 'name-thing'",
+            logging.Formatter, "{name-thing}", style="{"
+        )
+        # Testing failure for style mismatch
+        self.assert_error_message(
+            ValueError,
+            "invalid format: no fields",
+            logging.Formatter, '%(asctime)s', style='{'
+        )
+        # Testing failure for invalid conversion
+        self.assert_error_message(
+            ValueError,
+            "invalid conversion: 'Z'"
+        )
+        self.assertRaises(ValueError, logging.Formatter, '{asctime!s:#30,15f}', style='{')
+        self.assert_error_message(
+            ValueError,
+            "invalid format: expected ':' after conversion specifier",
+            logging.Formatter, '{asctime!aa:15}', style='{'
+        )
+        # Testing failure for invalid spec
+        self.assert_error_message(
+            ValueError,
+            "invalid format: bad specifier: '.2ff'",
+            logging.Formatter, '{process:.2ff}', style='{'
+        )
+        self.assertRaises(ValueError, logging.Formatter, '{process:.2Z}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{process!s:<##30,12g}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{process!s:<#30#,12g}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{process!s:{{w}},{{p}}}', style='{')
+        # Testing failure for mismatch braces
+        self.assert_error_message(
+            ValueError,
+            "invalid format: expected '}' before end of string",
+            logging.Formatter, '{process', style='{'
+        )
+        self.assert_error_message(
+            ValueError,
+            "invalid format: Single '}' encountered in format string",
+            logging.Formatter, 'process}', style='{'
+        )
+        self.assertRaises(ValueError, logging.Formatter, '{{foo!r:4.2}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{{foo!r:4.2}}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo/bar}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo:{{w}}.{{p}}}}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo!X:{{w}}.{{p}}}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo!a:random}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo!a:ran{dom}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo!a:ran{d}om}', style='{')
+        self.assertRaises(ValueError, logging.Formatter, '{foo.!a:d}', style='{')
+
+        # Dollar style
+        # Testing failure for mismatch bare $
+        self.assert_error_message(
+            ValueError,
+            "invalid format: bare \'$\' not allowed",
+            logging.Formatter, '$bar $$$', style='$'
+        )
+        self.assert_error_message(
+            ValueError,
+            "invalid format: bare \'$\' not allowed",
+            logging.Formatter, 'bar $', style='$'
+        )
+        self.assert_error_message(
+            ValueError,
+            "invalid format: bare \'$\' not allowed",
+            logging.Formatter, 'foo $.', style='$'
+        )
+        # Testing failure for mismatch style
+        self.assert_error_message(
+            ValueError,
+            "invalid format: no fields",
+            logging.Formatter, '{asctime}', style='$'
+        )
+        self.assertRaises(ValueError, logging.Formatter, '%(asctime)s', style='$')
+
+        # Testing failure for incorrect fields
+        self.assert_error_message(
+            ValueError,
+            "invalid format: no fields",
+            logging.Formatter, 'foo', style='$'
+        )
+        self.assertRaises(ValueError, logging.Formatter, '${asctime', style='$')
+
+    def test_defaults_parameter(self):
+        fmts = ['%(custom)s %(message)s', '{custom} {message}', '$custom $message']
+        styles = ['%', '{', '$']
+        for fmt, style in zip(fmts, styles):
+            f = logging.Formatter(fmt, style=style, defaults={'custom': 'Default'})
+            r = self.get_record()
+            self.assertEqual(f.format(r), 'Default Message with 2 placeholders')
+            r = self.get_record("custom")
+            self.assertEqual(f.format(r), '1234 Message with 2 placeholders')
+
+            # Without default
+            f = logging.Formatter(fmt, style=style)
+            r = self.get_record()
+            self.assertRaises(ValueError, f.format, r)
+
+            # Non-existing default is ignored
+            f = logging.Formatter(fmt, style=style, defaults={'Non-existing': 'Default'})
+            r = self.get_record("custom")
+            self.assertEqual(f.format(r), '1234 Message with 2 placeholders')
+
+    def test_invalid_style(self):
+        self.assertRaises(ValueError, logging.Formatter, None, None, 'x')
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_time(self):
+        r = self.get_record()
+        dt = datetime.datetime(1993, 4, 21, 8, 3, 0, 0, utc)
+        # We use None to indicate we want the local timezone
+        # We're essentially converting a UTC time to local time
+        r.created = time.mktime(dt.astimezone(None).timetuple())
+        r.msecs = 123
+        f = logging.Formatter('%(asctime)s %(message)s')
+        f.converter = time.gmtime
+        self.assertEqual(f.formatTime(r), '1993-04-21 08:03:00,123')
+        self.assertEqual(f.formatTime(r, '%Y:%d'), '1993:21')
+        f.format(r)
+        self.assertEqual(r.asctime, '1993-04-21 08:03:00,123')
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_default_msec_format_none(self):
+        class NoMsecFormatter(logging.Formatter):
+            default_msec_format = None
+            default_time_format = '%d/%m/%Y %H:%M:%S'
+
+        r = self.get_record()
+        dt = datetime.datetime(1993, 4, 21, 8, 3, 0, 123, utc)
+        r.created = time.mktime(dt.astimezone(None).timetuple())
+        f = NoMsecFormatter()
+        f.converter = time.gmtime
+        self.assertEqual(f.formatTime(r), '21/04/1993 08:03:00')
+
+    def test_issue_89047(self):
+        f = logging.Formatter(fmt='{asctime}.{msecs:03.0f} {message}', style='{', datefmt="%Y-%m-%d %H:%M:%S")
+        for i in range(2500):
+            time.sleep(0.0004)
+            r = logging.makeLogRecord({'msg': 'Message %d' % (i + 1)})
+            s = f.format(r)
+            self.assertNotIn('.1000', s)
+
+
+class TestBufferingFormatter(logging.BufferingFormatter):
+    def formatHeader(self, records):
+        return '[(%d)' % len(records)
+
+    def formatFooter(self, records):
+        return '(%d)]' % len(records)
+
+class BufferingFormatterTest(unittest.TestCase):
+    def setUp(self):
+        self.records = [
+            logging.makeLogRecord({'msg': 'one'}),
+            logging.makeLogRecord({'msg': 'two'}),
+        ]
+
+    def test_default(self):
+        f = logging.BufferingFormatter()
+        self.assertEqual('', f.format([]))
+        self.assertEqual('onetwo', f.format(self.records))
+
+    def test_custom(self):
+        f = TestBufferingFormatter()
+        self.assertEqual('[(2)onetwo(2)]', f.format(self.records))
+        lf = logging.Formatter('<%(message)s>')
+        f = TestBufferingFormatter(lf)
+        self.assertEqual('[(2)<one><two>(2)]', f.format(self.records))
+
+class ExceptionTest(BaseTest):
+    def test_formatting(self):
+        r = self.root_logger
+        h = RecordingHandler()
+        r.addHandler(h)
+        try:
+            raise RuntimeError('deliberate mistake')
+        except:
+            logging.exception('failed', stack_info=True)
+        r.removeHandler(h)
+        h.close()
+        r = h.records[0]
+        self.assertTrue(r.exc_text.startswith('Traceback (most recent '
+                                              'call last):\n'))
+        self.assertTrue(r.exc_text.endswith('\nRuntimeError: '
+                                            'deliberate mistake'))
+        self.assertTrue(r.stack_info.startswith('Stack (most recent '
+                                                'call last):\n'))
+        self.assertTrue(r.stack_info.endswith('logging.exception(\'failed\', '
+                                              'stack_info=True)'))
+
+
+class LastResortTest(BaseTest):
+    def test_last_resort(self):
+        # Test the last resort handler
+        root = self.root_logger
+        root.removeHandler(self.root_hdlr)
+        old_lastresort = logging.lastResort
+        old_raise_exceptions = logging.raiseExceptions
+
+        try:
+            with support.captured_stderr() as stderr:
+                root.debug('This should not appear')
+                self.assertEqual(stderr.getvalue(), '')
+                root.warning('Final chance!')
+                self.assertEqual(stderr.getvalue(), 'Final chance!\n')
+
+            # No handlers and no last resort, so 'No handlers' message
+            logging.lastResort = None
+            with support.captured_stderr() as stderr:
+                root.warning('Final chance!')
+                msg = 'No handlers could be found for logger "root"\n'
+                self.assertEqual(stderr.getvalue(), msg)
+
+            # 'No handlers' message only printed once
+            with support.captured_stderr() as stderr:
+                root.warning('Final chance!')
+                self.assertEqual(stderr.getvalue(), '')
+
+            # If raiseExceptions is False, no message is printed
+            root.manager.emittedNoHandlerWarning = False
+            logging.raiseExceptions = False
+            with support.captured_stderr() as stderr:
+                root.warning('Final chance!')
+                self.assertEqual(stderr.getvalue(), '')
+        finally:
+            root.addHandler(self.root_hdlr)
+            logging.lastResort = old_lastresort
+            logging.raiseExceptions = old_raise_exceptions
+
+
+class FakeHandler:
+
+    def __init__(self, identifier, called):
+        for method in ('acquire', 'flush', 'close', 'release'):
+            setattr(self, method, self.record_call(identifier, method, called))
+
+    def record_call(self, identifier, method_name, called):
+        def inner():
+            called.append('{} - {}'.format(identifier, method_name))
+        return inner
+
+
+class RecordingHandler(logging.NullHandler):
+
+    def __init__(self, *args, **kwargs):
+        super(RecordingHandler, self).__init__(*args, **kwargs)
+        self.records = []
+
+    def handle(self, record):
+        """Keep track of all the emitted records."""
+        self.records.append(record)
+
+
+class ShutdownTest(BaseTest):
+
+    """Test suite for the shutdown method."""
+
+    def setUp(self):
+        super(ShutdownTest, self).setUp()
+        self.called = []
+
+        raise_exceptions = logging.raiseExceptions
+        self.addCleanup(setattr, logging, 'raiseExceptions', raise_exceptions)
+
+    def raise_error(self, error):
+        def inner():
+            raise error()
+        return inner
+
+    def test_no_failure(self):
+        # create some fake handlers
+        handler0 = FakeHandler(0, self.called)
+        handler1 = FakeHandler(1, self.called)
+        handler2 = FakeHandler(2, self.called)
+
+        # create live weakref to those handlers
+        handlers = map(logging.weakref.ref, [handler0, handler1, handler2])
+
+        logging.shutdown(handlerList=list(handlers))
+
+        expected = ['2 - acquire', '2 - flush', '2 - close', '2 - release',
+                    '1 - acquire', '1 - flush', '1 - close', '1 - release',
+                    '0 - acquire', '0 - flush', '0 - close', '0 - release']
+        self.assertEqual(expected, self.called)
+
+    def _test_with_failure_in_method(self, method, error):
+        handler = FakeHandler(0, self.called)
+        setattr(handler, method, self.raise_error(error))
+        handlers = [logging.weakref.ref(handler)]
+
+        logging.shutdown(handlerList=list(handlers))
+
+        self.assertEqual('0 - release', self.called[-1])
+
+    def test_with_ioerror_in_acquire(self):
+        self._test_with_failure_in_method('acquire', OSError)
+
+    def test_with_ioerror_in_flush(self):
+        self._test_with_failure_in_method('flush', OSError)
+
+    def test_with_ioerror_in_close(self):
+        self._test_with_failure_in_method('close', OSError)
+
+    def test_with_valueerror_in_acquire(self):
+        self._test_with_failure_in_method('acquire', ValueError)
+
+    def test_with_valueerror_in_flush(self):
+        self._test_with_failure_in_method('flush', ValueError)
+
+    def test_with_valueerror_in_close(self):
+        self._test_with_failure_in_method('close', ValueError)
+
+    def test_with_other_error_in_acquire_without_raise(self):
+        logging.raiseExceptions = False
+        self._test_with_failure_in_method('acquire', IndexError)
+
+    def test_with_other_error_in_flush_without_raise(self):
+        logging.raiseExceptions = False
+        self._test_with_failure_in_method('flush', IndexError)
+
+    def test_with_other_error_in_close_without_raise(self):
+        logging.raiseExceptions = False
+        self._test_with_failure_in_method('close', IndexError)
+
+    def test_with_other_error_in_acquire_with_raise(self):
+        logging.raiseExceptions = True
+        self.assertRaises(IndexError, self._test_with_failure_in_method,
+                          'acquire', IndexError)
+
+    def test_with_other_error_in_flush_with_raise(self):
+        logging.raiseExceptions = True
+        self.assertRaises(IndexError, self._test_with_failure_in_method,
+                          'flush', IndexError)
+
+    def test_with_other_error_in_close_with_raise(self):
+        logging.raiseExceptions = True
+        self.assertRaises(IndexError, self._test_with_failure_in_method,
+                          'close', IndexError)
+
+
+class ModuleLevelMiscTest(BaseTest):
+
+    """Test suite for some module level methods."""
+
+    def test_disable(self):
+        old_disable = logging.root.manager.disable
+        # confirm our assumptions are correct
+        self.assertEqual(old_disable, 0)
+        self.addCleanup(logging.disable, old_disable)
+
+        logging.disable(83)
+        self.assertEqual(logging.root.manager.disable, 83)
+
+        self.assertRaises(ValueError, logging.disable, "doesnotexists")
+
+        class _NotAnIntOrString:
+            pass
+
+        self.assertRaises(TypeError, logging.disable, _NotAnIntOrString())
+
+        logging.disable("WARN")
+
+        # test the default value introduced in 3.7
+        # (Issue #28524)
+        logging.disable()
+        self.assertEqual(logging.root.manager.disable, logging.CRITICAL)
+
+    def _test_log(self, method, level=None):
+        called = []
+        support.patch(self, logging, 'basicConfig',
+                      lambda *a, **kw: called.append((a, kw)))
+
+        recording = RecordingHandler()
+        logging.root.addHandler(recording)
+
+        log_method = getattr(logging, method)
+        if level is not None:
+            log_method(level, "test me: %r", recording)
+        else:
+            log_method("test me: %r", recording)
+
+        self.assertEqual(len(recording.records), 1)
+        record = recording.records[0]
+        self.assertEqual(record.getMessage(), "test me: %r" % recording)
+
+        expected_level = level if level is not None else getattr(logging, method.upper())
+        self.assertEqual(record.levelno, expected_level)
+
+        # basicConfig was not called!
+        self.assertEqual(called, [])
+
+    def test_log(self):
+        self._test_log('log', logging.ERROR)
+
+    def test_debug(self):
+        self._test_log('debug')
+
+    def test_info(self):
+        self._test_log('info')
+
+    def test_warning(self):
+        self._test_log('warning')
+
+    def test_error(self):
+        self._test_log('error')
+
+    def test_critical(self):
+        self._test_log('critical')
+
+    def test_set_logger_class(self):
+        self.assertRaises(TypeError, logging.setLoggerClass, object)
+
+        class MyLogger(logging.Logger):
+            pass
+
+        logging.setLoggerClass(MyLogger)
+        self.assertEqual(logging.getLoggerClass(), MyLogger)
+
+        logging.setLoggerClass(logging.Logger)
+        self.assertEqual(logging.getLoggerClass(), logging.Logger)
+
+    def test_subclass_logger_cache(self):
+        # bpo-37258
+        message = []
+
+        class MyLogger(logging.getLoggerClass()):
+            def __init__(self, name='MyLogger', level=logging.NOTSET):
+                super().__init__(name, level)
+                message.append('initialized')
+
+        logging.setLoggerClass(MyLogger)
+        logger = logging.getLogger('just_some_logger')
+        self.assertEqual(message, ['initialized'])
+        stream = io.StringIO()
+        h = logging.StreamHandler(stream)
+        logger.addHandler(h)
+        try:
+            logger.setLevel(logging.DEBUG)
+            logger.debug("hello")
+            self.assertEqual(stream.getvalue().strip(), "hello")
+
+            stream.truncate(0)
+            stream.seek(0)
+
+            logger.setLevel(logging.INFO)
+            logger.debug("hello")
+            self.assertEqual(stream.getvalue(), "")
+        finally:
+            logger.removeHandler(h)
+            h.close()
+            logging.setLoggerClass(logging.Logger)
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_logging_at_shutdown(self):
+        # bpo-20037: Doing text I/O late at interpreter shutdown must not crash
+        code = textwrap.dedent("""
+            import logging
+
+            class A:
+                def __del__(self):
+                    try:
+                        raise ValueError("some error")
+                    except Exception:
+                        logging.exception("exception in __del__")
+
+            a = A()
+        """)
+        rc, out, err = assert_python_ok("-c", code)
+        err = err.decode()
+        self.assertIn("exception in __del__", err)
+        self.assertIn("ValueError: some error", err)
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_logging_at_shutdown_open(self):
+        # bpo-26789: FileHandler keeps a reference to the builtin open()
+        # function to be able to open or reopen the file during Python
+        # finalization.
+        filename = os_helper.TESTFN
+        self.addCleanup(os_helper.unlink, filename)
+
+        code = textwrap.dedent(f"""
+            import builtins
+            import logging
+
+            class A:
+                def __del__(self):
+                    logging.error("log in __del__")
+
+            # basicConfig() opens the file, but logging.shutdown() closes
+            # it at Python exit. When A.__del__() is called,
+            # FileHandler._open() must be called again to re-open the file.
+            logging.basicConfig(filename={filename!r}, encoding="utf-8")
+
+            a = A()
+
+            # Simulate the Python finalization which removes the builtin
+            # open() function.
+            del builtins.open
+        """)
+        assert_python_ok("-c", code)
+
+        with open(filename, encoding="utf-8") as fp:
+            self.assertEqual(fp.read().rstrip(), "ERROR:root:log in __del__")
+
+    def test_recursion_error(self):
+        # Issue 36272
+        code = textwrap.dedent("""
+            import logging
+
+            def rec():
+                logging.error("foo")
+                rec()
+
+            rec()
+        """)
+        rc, out, err = assert_python_failure("-c", code)
+        err = err.decode()
+        self.assertNotIn("Cannot recover from stack overflow.", err)
+        self.assertEqual(rc, 1)
+
+    def test_get_level_names_mapping(self):
+        mapping = logging.getLevelNamesMapping()
+        self.assertEqual(logging._nameToLevel, mapping)  # value is equivalent
+        self.assertIsNot(logging._nameToLevel, mapping)  # but not the internal data
+        new_mapping = logging.getLevelNamesMapping()     # another call -> another copy
+        self.assertIsNot(mapping, new_mapping)           # verify not the same object as before
+        self.assertEqual(mapping, new_mapping)           # but equivalent in value
+
+
+class LogRecordTest(BaseTest):
+    def test_str_rep(self):
+        r = logging.makeLogRecord({})
+        s = str(r)
+        self.assertTrue(s.startswith('<LogRecord: '))
+        self.assertTrue(s.endswith('>'))
+
+    def test_dict_arg(self):
+        h = RecordingHandler()
+        r = logging.getLogger()
+        r.addHandler(h)
+        d = {'less' : 'more' }
+        logging.warning('less is %(less)s', d)
+        self.assertIs(h.records[0].args, d)
+        self.assertEqual(h.records[0].message, 'less is more')
+        r.removeHandler(h)
+        h.close()
+
+    @staticmethod # pickled as target of child process in the following test
+    def _extract_logrecord_process_name(key, logMultiprocessing, conn=None):
+        prev_logMultiprocessing = logging.logMultiprocessing
+        logging.logMultiprocessing = logMultiprocessing
+        try:
+            import multiprocessing as mp
+            name = mp.current_process().name
+
+            r1 = logging.makeLogRecord({'msg': f'msg1_{key}'})
+
+            # https://bugs.python.org/issue45128
+            with support.swap_item(sys.modules, 'multiprocessing', None):
+                r2 = logging.makeLogRecord({'msg': f'msg2_{key}'})
+
+            results = {'processName'  : name,
+                       'r1.processName': r1.processName,
+                       'r2.processName': r2.processName,
+                       }
+        finally:
+            logging.logMultiprocessing = prev_logMultiprocessing
+        if conn:
+            conn.send(results)
+        else:
+            return results
+
+    def test_multiprocessing(self):
+        support.skip_if_broken_multiprocessing_synchronize()
+        multiprocessing_imported = 'multiprocessing' in sys.modules
+        try:
+            # logMultiprocessing is True by default
+            self.assertEqual(logging.logMultiprocessing, True)
+
+            LOG_MULTI_PROCESSING = True
+            # When logMultiprocessing == True:
+            # In the main process processName = 'MainProcess'
+            r = logging.makeLogRecord({})
+            self.assertEqual(r.processName, 'MainProcess')
+
+            results = self._extract_logrecord_process_name(1, LOG_MULTI_PROCESSING)
+            self.assertEqual('MainProcess', results['processName'])
+            self.assertEqual('MainProcess', results['r1.processName'])
+            self.assertEqual('MainProcess', results['r2.processName'])
+
+            # In other processes, processName is correct when multiprocessing in imported,
+            # but it is (incorrectly) defaulted to 'MainProcess' otherwise (bpo-38762).
+            import multiprocessing
+            parent_conn, child_conn = multiprocessing.Pipe()
+            p = multiprocessing.Process(
+                target=self._extract_logrecord_process_name,
+                args=(2, LOG_MULTI_PROCESSING, child_conn,)
+            )
+            p.start()
+            results = parent_conn.recv()
+            self.assertNotEqual('MainProcess', results['processName'])
+            self.assertEqual(results['processName'], results['r1.processName'])
+            self.assertEqual('MainProcess', results['r2.processName'])
+            p.join()
+
+        finally:
+            if multiprocessing_imported:
+                import multiprocessing
+
+    def test_optional(self):
+        NONE = self.assertIsNone
+        NOT_NONE = self.assertIsNotNone
+
+        r = logging.makeLogRecord({})
+        NOT_NONE(r.thread)
+        NOT_NONE(r.threadName)
+        NOT_NONE(r.process)
+        NOT_NONE(r.processName)
+        NONE(r.taskName)
+        log_threads = logging.logThreads
+        log_processes = logging.logProcesses
+        log_multiprocessing = logging.logMultiprocessing
+        log_asyncio_tasks = logging.logAsyncioTasks
+        try:
+            logging.logThreads = False
+            logging.logProcesses = False
+            logging.logMultiprocessing = False
+            logging.logAsyncioTasks = False
+            r = logging.makeLogRecord({})
+
+            NONE(r.thread)
+            NONE(r.threadName)
+            NONE(r.process)
+            NONE(r.processName)
+            NONE(r.taskName)
+        finally:
+            logging.logThreads = log_threads
+            logging.logProcesses = log_processes
+            logging.logMultiprocessing = log_multiprocessing
+            logging.logAsyncioTasks = log_asyncio_tasks
+
+    async def _make_record_async(self, assertion):
+        r = logging.makeLogRecord({})
+        assertion(r.taskName)
+
+    @support.requires_working_socket()
+    def test_taskName_with_asyncio_imported(self):
+        try:
+            make_record = self._make_record_async
+            with asyncio.Runner() as runner:
+                logging.logAsyncioTasks = True
+                runner.run(make_record(self.assertIsNotNone))
+                logging.logAsyncioTasks = False
+                runner.run(make_record(self.assertIsNone))
+        finally:
+            asyncio.set_event_loop_policy(None)
+
+    @support.requires_working_socket()
+    def test_taskName_without_asyncio_imported(self):
+        try:
+            make_record = self._make_record_async
+            with asyncio.Runner() as runner, support.swap_item(sys.modules, 'asyncio', None):
+                logging.logAsyncioTasks = True
+                runner.run(make_record(self.assertIsNone))
+                logging.logAsyncioTasks = False
+                runner.run(make_record(self.assertIsNone))
+        finally:
+            asyncio.set_event_loop_policy(None)
+
+
+class BasicConfigTest(unittest.TestCase):
+
+    """Test suite for logging.basicConfig."""
+
+    def setUp(self):
+        super(BasicConfigTest, self).setUp()
+        self.handlers = logging.root.handlers
+        self.saved_handlers = logging._handlers.copy()
+        self.saved_handler_list = logging._handlerList[:]
+        self.original_logging_level = logging.root.level
+        self.addCleanup(self.cleanup)
+        logging.root.handlers = []
+
+    def tearDown(self):
+        for h in logging.root.handlers[:]:
+            logging.root.removeHandler(h)
+            h.close()
+        super(BasicConfigTest, self).tearDown()
+
+    def cleanup(self):
+        setattr(logging.root, 'handlers', self.handlers)
+        logging._handlers.clear()
+        logging._handlers.update(self.saved_handlers)
+        logging._handlerList[:] = self.saved_handler_list
+        logging.root.setLevel(self.original_logging_level)
+
+    def test_no_kwargs(self):
+        logging.basicConfig()
+
+        # handler defaults to a StreamHandler to sys.stderr
+        self.assertEqual(len(logging.root.handlers), 1)
+        handler = logging.root.handlers[0]
+        self.assertIsInstance(handler, logging.StreamHandler)
+        self.assertEqual(handler.stream, sys.stderr)
+
+        formatter = handler.formatter
+        # format defaults to logging.BASIC_FORMAT
+        self.assertEqual(formatter._style._fmt, logging.BASIC_FORMAT)
+        # datefmt defaults to None
+        self.assertIsNone(formatter.datefmt)
+        # style defaults to %
+        self.assertIsInstance(formatter._style, logging.PercentStyle)
+
+        # level is not explicitly set
+        self.assertEqual(logging.root.level, self.original_logging_level)
+
+    def test_strformatstyle(self):
+        with support.captured_stdout() as output:
+            logging.basicConfig(stream=sys.stdout, style="{")
+            logging.error("Log an error")
+            sys.stdout.seek(0)
+            self.assertEqual(output.getvalue().strip(),
+                             "ERROR:root:Log an error")
+
+    def test_stringtemplatestyle(self):
+        with support.captured_stdout() as output:
+            logging.basicConfig(stream=sys.stdout, style="$")
+            logging.error("Log an error")
+            sys.stdout.seek(0)
+            self.assertEqual(output.getvalue().strip(),
+                             "ERROR:root:Log an error")
+
+    def test_filename(self):
+
+        def cleanup(h1, h2, fn):
+            h1.close()
+            h2.close()
+            os.remove(fn)
+
+        logging.basicConfig(filename='test.log', encoding='utf-8')
+
+        self.assertEqual(len(logging.root.handlers), 1)
+        handler = logging.root.handlers[0]
+        self.assertIsInstance(handler, logging.FileHandler)
+
+        expected = logging.FileHandler('test.log', 'a', encoding='utf-8')
+        self.assertEqual(handler.stream.mode, expected.stream.mode)
+        self.assertEqual(handler.stream.name, expected.stream.name)
+        self.addCleanup(cleanup, handler, expected, 'test.log')
+
+    def test_filemode(self):
+
+        def cleanup(h1, h2, fn):
+            h1.close()
+            h2.close()
+            os.remove(fn)
+
+        logging.basicConfig(filename='test.log', filemode='wb')
+
+        handler = logging.root.handlers[0]
+        expected = logging.FileHandler('test.log', 'wb')
+        self.assertEqual(handler.stream.mode, expected.stream.mode)
+        self.addCleanup(cleanup, handler, expected, 'test.log')
+
+    def test_stream(self):
+        stream = io.StringIO()
+        self.addCleanup(stream.close)
+        logging.basicConfig(stream=stream)
+
+        self.assertEqual(len(logging.root.handlers), 1)
+        handler = logging.root.handlers[0]
+        self.assertIsInstance(handler, logging.StreamHandler)
+        self.assertEqual(handler.stream, stream)
+
+    def test_format(self):
+        logging.basicConfig(format='%(asctime)s - %(message)s')
+
+        formatter = logging.root.handlers[0].formatter
+        self.assertEqual(formatter._style._fmt, '%(asctime)s - %(message)s')
+
+    def test_datefmt(self):
+        logging.basicConfig(datefmt='bar')
+
+        formatter = logging.root.handlers[0].formatter
+        self.assertEqual(formatter.datefmt, 'bar')
+
+    def test_style(self):
+        logging.basicConfig(style='$')
+
+        formatter = logging.root.handlers[0].formatter
+        self.assertIsInstance(formatter._style, logging.StringTemplateStyle)
+
+    def test_level(self):
+        old_level = logging.root.level
+        self.addCleanup(logging.root.setLevel, old_level)
+
+        logging.basicConfig(level=57)
+        self.assertEqual(logging.root.level, 57)
+        # Test that second call has no effect
+        logging.basicConfig(level=58)
+        self.assertEqual(logging.root.level, 57)
+
+    def test_incompatible(self):
+        assertRaises = self.assertRaises
+        handlers = [logging.StreamHandler()]
+        stream = sys.stderr
+        assertRaises(ValueError, logging.basicConfig, filename='test.log',
+                     stream=stream)
+        assertRaises(ValueError, logging.basicConfig, filename='test.log',
+                     handlers=handlers)
+        assertRaises(ValueError, logging.basicConfig, stream=stream,
+                     handlers=handlers)
+        # Issue 23207: test for invalid kwargs
+        assertRaises(ValueError, logging.basicConfig, loglevel=logging.INFO)
+        # Should pop both filename and filemode even if filename is None
+        logging.basicConfig(filename=None, filemode='a')
+
+    def test_handlers(self):
+        handlers = [
+            logging.StreamHandler(),
+            logging.StreamHandler(sys.stdout),
+            logging.StreamHandler(),
+        ]
+        f = logging.Formatter()
+        handlers[2].setFormatter(f)
+        logging.basicConfig(handlers=handlers)
+        self.assertIs(handlers[0], logging.root.handlers[0])
+        self.assertIs(handlers[1], logging.root.handlers[1])
+        self.assertIs(handlers[2], logging.root.handlers[2])
+        self.assertIsNotNone(handlers[0].formatter)
+        self.assertIsNotNone(handlers[1].formatter)
+        self.assertIs(handlers[2].formatter, f)
+        self.assertIs(handlers[0].formatter, handlers[1].formatter)
+
+    def test_force(self):
+        old_string_io = io.StringIO()
+        new_string_io = io.StringIO()
+        old_handlers = [logging.StreamHandler(old_string_io)]
+        new_handlers = [logging.StreamHandler(new_string_io)]
+        logging.basicConfig(level=logging.WARNING, handlers=old_handlers)
+        logging.warning('warn')
+        logging.info('info')
+        logging.debug('debug')
+        self.assertEqual(len(logging.root.handlers), 1)
+        logging.basicConfig(level=logging.INFO, handlers=new_handlers,
+                            force=True)
+        logging.warning('warn')
+        logging.info('info')
+        logging.debug('debug')
+        self.assertEqual(len(logging.root.handlers), 1)
+        self.assertEqual(old_string_io.getvalue().strip(),
+                         'WARNING:root:warn')
+        self.assertEqual(new_string_io.getvalue().strip(),
+                         'WARNING:root:warn\nINFO:root:info')
+
+    def test_encoding(self):
+        try:
+            encoding = 'utf-8'
+            logging.basicConfig(filename='test.log', encoding=encoding,
+                                errors='strict',
+                                format='%(message)s', level=logging.DEBUG)
+
+            self.assertEqual(len(logging.root.handlers), 1)
+            handler = logging.root.handlers[0]
+            self.assertIsInstance(handler, logging.FileHandler)
+            self.assertEqual(handler.encoding, encoding)
+            logging.debug('The Øresund Bridge joins Copenhagen to Malmö')
+        finally:
+            handler.close()
+            with open('test.log', encoding='utf-8') as f:
+                data = f.read().strip()
+            os.remove('test.log')
+            self.assertEqual(data,
+                             'The Øresund Bridge joins Copenhagen to Malmö')
+
+    def test_encoding_errors(self):
+        try:
+            encoding = 'ascii'
+            logging.basicConfig(filename='test.log', encoding=encoding,
+                                errors='ignore',
+                                format='%(message)s', level=logging.DEBUG)
+
+            self.assertEqual(len(logging.root.handlers), 1)
+            handler = logging.root.handlers[0]
+            self.assertIsInstance(handler, logging.FileHandler)
+            self.assertEqual(handler.encoding, encoding)
+            logging.debug('The Øresund Bridge joins Copenhagen to Malmö')
+        finally:
+            handler.close()
+            with open('test.log', encoding='utf-8') as f:
+                data = f.read().strip()
+            os.remove('test.log')
+            self.assertEqual(data, 'The resund Bridge joins Copenhagen to Malm')
+
+    def test_encoding_errors_default(self):
+        try:
+            encoding = 'ascii'
+            logging.basicConfig(filename='test.log', encoding=encoding,
+                                format='%(message)s', level=logging.DEBUG)
+
+            self.assertEqual(len(logging.root.handlers), 1)
+            handler = logging.root.handlers[0]
+            self.assertIsInstance(handler, logging.FileHandler)
+            self.assertEqual(handler.encoding, encoding)
+            self.assertEqual(handler.errors, 'backslashreplace')
+            logging.debug('😂: ☃️: The Øresund Bridge joins Copenhagen to Malmö')
+        finally:
+            handler.close()
+            with open('test.log', encoding='utf-8') as f:
+                data = f.read().strip()
+            os.remove('test.log')
+            self.assertEqual(data, r'\U0001f602: \u2603\ufe0f: The \xd8resund '
+                                   r'Bridge joins Copenhagen to Malm\xf6')
+
+    # TODO: RustPython
+    @unittest.expectedFailure
+    def test_encoding_errors_none(self):
+        # Specifying None should behave as 'strict'
+        try:
+            encoding = 'ascii'
+            logging.basicConfig(filename='test.log', encoding=encoding,
+                                errors=None,
+                                format='%(message)s', level=logging.DEBUG)
+
+            self.assertEqual(len(logging.root.handlers), 1)
+            handler = logging.root.handlers[0]
+            self.assertIsInstance(handler, logging.FileHandler)
+            self.assertEqual(handler.encoding, encoding)
+            self.assertIsNone(handler.errors)
+
+            message = []
+
+            def dummy_handle_error(record):
+                message.append(str(sys.exception()))
+
+            handler.handleError = dummy_handle_error
+            logging.debug('The Øresund Bridge joins Copenhagen to Malmö')
+            self.assertTrue(message)
+            self.assertIn("'ascii' codec can't encode "
+                          "character '\\xd8' in position 4:", message[0])
+        finally:
+            handler.close()
+            with open('test.log', encoding='utf-8') as f:
+                data = f.read().strip()
+            os.remove('test.log')
+            # didn't write anything due to the encoding error
+            self.assertEqual(data, r'')
+
+    @support.requires_working_socket()
+    def test_log_taskName(self):
+        async def log_record():
+            logging.warning('hello world')
+
+        handler = None
+        log_filename = make_temp_file('.log', 'test-logging-taskname-')
+        self.addCleanup(os.remove, log_filename)
+        try:
+            encoding = 'utf-8'
+            logging.basicConfig(filename=log_filename, errors='strict',
+                                encoding=encoding, level=logging.WARNING,
+                                format='%(taskName)s - %(message)s')
+
+            self.assertEqual(len(logging.root.handlers), 1)
+            handler = logging.root.handlers[0]
+            self.assertIsInstance(handler, logging.FileHandler)
+
+            with asyncio.Runner(debug=True) as runner:
+                logging.logAsyncioTasks = True
+                runner.run(log_record())
+            with open(log_filename, encoding='utf-8') as f:
+                data = f.read().strip()
+            self.assertRegex(data, r'Task-\d+ - hello world')
+        finally:
+            asyncio.set_event_loop_policy(None)
+            if handler:
+                handler.close()
+
+
+    def _test_log(self, method, level=None):
+        # logging.root has no handlers so basicConfig should be called
+        called = []
+
+        old_basic_config = logging.basicConfig
+        def my_basic_config(*a, **kw):
+            old_basic_config()
+            old_level = logging.root.level
+            logging.root.setLevel(100)  # avoid having messages in stderr
+            self.addCleanup(logging.root.setLevel, old_level)
+            called.append((a, kw))
+
+        support.patch(self, logging, 'basicConfig', my_basic_config)
+
+        log_method = getattr(logging, method)
+        if level is not None:
+            log_method(level, "test me")
+        else:
+            log_method("test me")
+
+        # basicConfig was called with no arguments
+        self.assertEqual(called, [((), {})])
+
+    def test_log(self):
+        self._test_log('log', logging.WARNING)
+
+    def test_debug(self):
+        self._test_log('debug')
+
+    def test_info(self):
+        self._test_log('info')
+
+    def test_warning(self):
+        self._test_log('warning')
+
+    def test_error(self):
+        self._test_log('error')
+
+    def test_critical(self):
+        self._test_log('critical')
+
+
+class LoggerAdapterTest(unittest.TestCase):
+    def setUp(self):
+        super(LoggerAdapterTest, self).setUp()
+        old_handler_list = logging._handlerList[:]
+
+        self.recording = RecordingHandler()
+        self.logger = logging.root
+        self.logger.addHandler(self.recording)
+        self.addCleanup(self.logger.removeHandler, self.recording)
+        self.addCleanup(self.recording.close)
+
+        def cleanup():
+            logging._handlerList[:] = old_handler_list
+
+        self.addCleanup(cleanup)
+        self.addCleanup(logging.shutdown)
+        self.adapter = logging.LoggerAdapter(logger=self.logger, extra=None)
+
+    def test_exception(self):
+        msg = 'testing exception: %r'
+        exc = None
+        try:
+            1 / 0
+        except ZeroDivisionError as e:
+            exc = e
+            self.adapter.exception(msg, self.recording)
+
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertEqual(record.levelno, logging.ERROR)
+        self.assertEqual(record.msg, msg)
+        self.assertEqual(record.args, (self.recording,))
+        self.assertEqual(record.exc_info,
+                         (exc.__class__, exc, exc.__traceback__))
+
+    def test_exception_excinfo(self):
+        try:
+            1 / 0
+        except ZeroDivisionError as e:
+            exc = e
+
+        self.adapter.exception('exc_info test', exc_info=exc)
+
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertEqual(record.exc_info,
+                         (exc.__class__, exc, exc.__traceback__))
+
+    def test_critical(self):
+        msg = 'critical test! %r'
+        self.adapter.critical(msg, self.recording)
+
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertEqual(record.levelno, logging.CRITICAL)
+        self.assertEqual(record.msg, msg)
+        self.assertEqual(record.args, (self.recording,))
+        self.assertEqual(record.funcName, 'test_critical')
+
+    def test_is_enabled_for(self):
+        old_disable = self.adapter.logger.manager.disable
+        self.adapter.logger.manager.disable = 33
+        self.addCleanup(setattr, self.adapter.logger.manager, 'disable',
+                        old_disable)
+        self.assertFalse(self.adapter.isEnabledFor(32))
+
+    def test_has_handlers(self):
+        self.assertTrue(self.adapter.hasHandlers())
+
+        for handler in self.logger.handlers:
+            self.logger.removeHandler(handler)
+
+        self.assertFalse(self.logger.hasHandlers())
+        self.assertFalse(self.adapter.hasHandlers())
+
+    def test_nested(self):
+        msg = 'Adapters can be nested, yo.'
+        adapter = PrefixAdapter(logger=self.logger, extra=None)
+        adapter_adapter = PrefixAdapter(logger=adapter, extra=None)
+        adapter_adapter.prefix = 'AdapterAdapter'
+        self.assertEqual(repr(adapter), repr(adapter_adapter))
+        adapter_adapter.log(logging.CRITICAL, msg, self.recording)
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertEqual(record.levelno, logging.CRITICAL)
+        self.assertEqual(record.msg, f"Adapter AdapterAdapter {msg}")
+        self.assertEqual(record.args, (self.recording,))
+        self.assertEqual(record.funcName, 'test_nested')
+        orig_manager = adapter_adapter.manager
+        self.assertIs(adapter.manager, orig_manager)
+        self.assertIs(self.logger.manager, orig_manager)
+        temp_manager = object()
+        try:
+            adapter_adapter.manager = temp_manager
+            self.assertIs(adapter_adapter.manager, temp_manager)
+            self.assertIs(adapter.manager, temp_manager)
+            self.assertIs(self.logger.manager, temp_manager)
+        finally:
+            adapter_adapter.manager = orig_manager
+        self.assertIs(adapter_adapter.manager, orig_manager)
+        self.assertIs(adapter.manager, orig_manager)
+        self.assertIs(self.logger.manager, orig_manager)
+
+    def test_styled_adapter(self):
+        # Test an example from the Cookbook.
+        records = self.recording.records
+        adapter = StyleAdapter(self.logger)
+        adapter.warning('Hello, {}!', 'world')
+        self.assertEqual(str(records[-1].msg), 'Hello, world!')
+        self.assertEqual(records[-1].funcName, 'test_styled_adapter')
+        adapter.log(logging.WARNING, 'Goodbye {}.', 'world')
+        self.assertEqual(str(records[-1].msg), 'Goodbye world.')
+        self.assertEqual(records[-1].funcName, 'test_styled_adapter')
+
+    def test_nested_styled_adapter(self):
+        records = self.recording.records
+        adapter = PrefixAdapter(self.logger)
+        adapter.prefix = '{}'
+        adapter2 = StyleAdapter(adapter)
+        adapter2.warning('Hello, {}!', 'world')
+        self.assertEqual(str(records[-1].msg), '{} Hello, world!')
+        self.assertEqual(records[-1].funcName, 'test_nested_styled_adapter')
+        adapter2.log(logging.WARNING, 'Goodbye {}.', 'world')
+        self.assertEqual(str(records[-1].msg), '{} Goodbye world.')
+        self.assertEqual(records[-1].funcName, 'test_nested_styled_adapter')
+
+    def test_find_caller_with_stacklevel(self):
+        the_level = 1
+        trigger = self.adapter.warning
+
+        def innermost():
+            trigger('test', stacklevel=the_level)
+
+        def inner():
+            innermost()
+
+        def outer():
+            inner()
+
+        records = self.recording.records
+        outer()
+        self.assertEqual(records[-1].funcName, 'innermost')
+        lineno = records[-1].lineno
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'inner')
+        self.assertGreater(records[-1].lineno, lineno)
+        lineno = records[-1].lineno
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'outer')
+        self.assertGreater(records[-1].lineno, lineno)
+        lineno = records[-1].lineno
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'test_find_caller_with_stacklevel')
+        self.assertGreater(records[-1].lineno, lineno)
+
+    def test_extra_in_records(self):
+        self.adapter = logging.LoggerAdapter(logger=self.logger,
+                                             extra={'foo': '1'})
+
+        self.adapter.critical('foo should be here')
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertTrue(hasattr(record, 'foo'))
+        self.assertEqual(record.foo, '1')
+
+    def test_extra_not_merged_by_default(self):
+        self.adapter.critical('foo should NOT be here', extra={'foo': 'nope'})
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertFalse(hasattr(record, 'foo'))
+
+
+class PrefixAdapter(logging.LoggerAdapter):
+    prefix = 'Adapter'
+
+    def process(self, msg, kwargs):
+        return f"{self.prefix} {msg}", kwargs
+
+
+class Message:
+    def __init__(self, fmt, args):
+        self.fmt = fmt
+        self.args = args
+
+    def __str__(self):
+        return self.fmt.format(*self.args)
+
+
+class StyleAdapter(logging.LoggerAdapter):
+    def log(self, level, msg, /, *args, stacklevel=1, **kwargs):
+        if self.isEnabledFor(level):
+            msg, kwargs = self.process(msg, kwargs)
+            self.logger.log(level, Message(msg, args), **kwargs,
+                            stacklevel=stacklevel+1)
+
+
+class LoggerTest(BaseTest, AssertErrorMessage):
+
+    def setUp(self):
+        super(LoggerTest, self).setUp()
+        self.recording = RecordingHandler()
+        self.logger = logging.Logger(name='blah')
+        self.logger.addHandler(self.recording)
+        self.addCleanup(self.logger.removeHandler, self.recording)
+        self.addCleanup(self.recording.close)
+        self.addCleanup(logging.shutdown)
+
+    def test_set_invalid_level(self):
+        self.assert_error_message(
+            TypeError, 'Level not an integer or a valid string: None',
+            self.logger.setLevel, None)
+        self.assert_error_message(
+            TypeError, 'Level not an integer or a valid string: (0, 0)',
+            self.logger.setLevel, (0, 0))
+
+    def test_exception(self):
+        msg = 'testing exception: %r'
+        exc = None
+        try:
+            1 / 0
+        except ZeroDivisionError as e:
+            exc = e
+            self.logger.exception(msg, self.recording)
+
+        self.assertEqual(len(self.recording.records), 1)
+        record = self.recording.records[0]
+        self.assertEqual(record.levelno, logging.ERROR)
+        self.assertEqual(record.msg, msg)
+        self.assertEqual(record.args, (self.recording,))
+        self.assertEqual(record.exc_info,
+                         (exc.__class__, exc, exc.__traceback__))
+
+    def test_log_invalid_level_with_raise(self):
+        with support.swap_attr(logging, 'raiseExceptions', True):
+            self.assertRaises(TypeError, self.logger.log, '10', 'test message')
+
+    def test_log_invalid_level_no_raise(self):
+        with support.swap_attr(logging, 'raiseExceptions', False):
+            self.logger.log('10', 'test message')  # no exception happens
+
+    def test_find_caller_with_stack_info(self):
+        called = []
+        support.patch(self, logging.traceback, 'print_stack',
+                      lambda f, file: called.append(file.getvalue()))
+
+        self.logger.findCaller(stack_info=True)
+
+        self.assertEqual(len(called), 1)
+        self.assertEqual('Stack (most recent call last):\n', called[0])
+
+    def test_find_caller_with_stacklevel(self):
+        the_level = 1
+        trigger = self.logger.warning
+
+        def innermost():
+            trigger('test', stacklevel=the_level)
+
+        def inner():
+            innermost()
+
+        def outer():
+            inner()
+
+        records = self.recording.records
+        outer()
+        self.assertEqual(records[-1].funcName, 'innermost')
+        lineno = records[-1].lineno
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'inner')
+        self.assertGreater(records[-1].lineno, lineno)
+        lineno = records[-1].lineno
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'outer')
+        self.assertGreater(records[-1].lineno, lineno)
+        lineno = records[-1].lineno
+        root_logger = logging.getLogger()
+        root_logger.addHandler(self.recording)
+        trigger = logging.warning
+        outer()
+        self.assertEqual(records[-1].funcName, 'outer')
+        root_logger.removeHandler(self.recording)
+        trigger = self.logger.warning
+        the_level += 1
+        outer()
+        self.assertEqual(records[-1].funcName, 'test_find_caller_with_stacklevel')
+        self.assertGreater(records[-1].lineno, lineno)
+
+    def test_make_record_with_extra_overwrite(self):
+        name = 'my record'
+        level = 13
+        fn = lno = msg = args = exc_info = func = sinfo = None
+        rv = logging._logRecordFactory(name, level, fn, lno, msg, args,
+                                       exc_info, func, sinfo)
+
+        for key in ('message', 'asctime') + tuple(rv.__dict__.keys()):
+            extra = {key: 'some value'}
+            self.assertRaises(KeyError, self.logger.makeRecord, name, level,
+                              fn, lno, msg, args, exc_info,
+                              extra=extra, sinfo=sinfo)
+
+    def test_make_record_with_extra_no_overwrite(self):
+        name = 'my record'
+        level = 13
+        fn = lno = msg = args = exc_info = func = sinfo = None
+        extra = {'valid_key': 'some value'}
+        result = self.logger.makeRecord(name, level, fn, lno, msg, args,
+                                        exc_info, extra=extra, sinfo=sinfo)
+        self.assertIn('valid_key', result.__dict__)
+
+    def test_has_handlers(self):
+        self.assertTrue(self.logger.hasHandlers())
+
+        for handler in self.logger.handlers:
+            self.logger.removeHandler(handler)
+        self.assertFalse(self.logger.hasHandlers())
+
+    def test_has_handlers_no_propagate(self):
+        child_logger = logging.getLogger('blah.child')
+        child_logger.propagate = False
+        self.assertFalse(child_logger.hasHandlers())
+
+    def test_is_enabled_for(self):
+        old_disable = self.logger.manager.disable
+        self.logger.manager.disable = 23
+        self.addCleanup(setattr, self.logger.manager, 'disable', old_disable)
+        self.assertFalse(self.logger.isEnabledFor(22))
+
+    def test_is_enabled_for_disabled_logger(self):
+        old_disabled = self.logger.disabled
+        old_disable = self.logger.manager.disable
+
+        self.logger.disabled = True
+        self.logger.manager.disable = 21
+
+        self.addCleanup(setattr, self.logger, 'disabled', old_disabled)
+        self.addCleanup(setattr, self.logger.manager, 'disable', old_disable)
+
+        self.assertFalse(self.logger.isEnabledFor(22))
+
+    def test_root_logger_aliases(self):
+        root = logging.getLogger()
+        self.assertIs(root, logging.root)
+        self.assertIs(root, logging.getLogger(None))
+        self.assertIs(root, logging.getLogger(''))
+        self.assertIs(root, logging.getLogger('root'))
+        self.assertIs(root, logging.getLogger('foo').root)
+        self.assertIs(root, logging.getLogger('foo.bar').root)
+        self.assertIs(root, logging.getLogger('foo').parent)
+
+        self.assertIsNot(root, logging.getLogger('\0'))
+        self.assertIsNot(root, logging.getLogger('foo.bar').parent)
+
+    def test_invalid_names(self):
+        self.assertRaises(TypeError, logging.getLogger, any)
+        self.assertRaises(TypeError, logging.getLogger, b'foo')
+
+    def test_pickling(self):
+        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
+            for name in ('', 'root', 'foo', 'foo.bar', 'baz.bar'):
+                logger = logging.getLogger(name)
+                s = pickle.dumps(logger, proto)
+                unpickled = pickle.loads(s)
+                self.assertIs(unpickled, logger)
+
+    def test_caching(self):
+        root = self.root_logger
+        logger1 = logging.getLogger("abc")
+        logger2 = logging.getLogger("abc.def")
+
+        # Set root logger level and ensure cache is empty
+        root.setLevel(logging.ERROR)
+        self.assertEqual(logger2.getEffectiveLevel(), logging.ERROR)
+        self.assertEqual(logger2._cache, {})
+
+        # Ensure cache is populated and calls are consistent
+        self.assertTrue(logger2.isEnabledFor(logging.ERROR))
+        self.assertFalse(logger2.isEnabledFor(logging.DEBUG))
+        self.assertEqual(logger2._cache, {logging.ERROR: True, logging.DEBUG: False})
+        self.assertEqual(root._cache, {})
+        self.assertTrue(logger2.isEnabledFor(logging.ERROR))
+
+        # Ensure root cache gets populated
+        self.assertEqual(root._cache, {})
+        self.assertTrue(root.isEnabledFor(logging.ERROR))
+        self.assertEqual(root._cache, {logging.ERROR: True})
+
+        # Set parent logger level and ensure caches are emptied
+        logger1.setLevel(logging.CRITICAL)
+        self.assertEqual(logger2.getEffectiveLevel(), logging.CRITICAL)
+        self.assertEqual(logger2._cache, {})
+
+        # Ensure logger2 uses parent logger's effective level
+        self.assertFalse(logger2.isEnabledFor(logging.ERROR))
+
+        # Set level to NOTSET and ensure caches are empty
+        logger2.setLevel(logging.NOTSET)
+        self.assertEqual(logger2.getEffectiveLevel(), logging.CRITICAL)
+        self.assertEqual(logger2._cache, {})
+        self.assertEqual(logger1._cache, {})
+        self.assertEqual(root._cache, {})
+
+        # Verify logger2 follows parent and not root
+        self.assertFalse(logger2.isEnabledFor(logging.ERROR))
+        self.assertTrue(logger2.isEnabledFor(logging.CRITICAL))
+        self.assertFalse(logger1.isEnabledFor(logging.ERROR))
+        self.assertTrue(logger1.isEnabledFor(logging.CRITICAL))
+        self.assertTrue(root.isEnabledFor(logging.ERROR))
+
+        # Disable logging in manager and ensure caches are clear
+        logging.disable()
+        self.assertEqual(logger2.getEffectiveLevel(), logging.CRITICAL)
+        self.assertEqual(logger2._cache, {})
+        self.assertEqual(logger1._cache, {})
+        self.assertEqual(root._cache, {})
+
+        # Ensure no loggers are enabled
+        self.assertFalse(logger1.isEnabledFor(logging.CRITICAL))
+        self.assertFalse(logger2.isEnabledFor(logging.CRITICAL))
+        self.assertFalse(root.isEnabledFor(logging.CRITICAL))
+
+
+class BaseFileTest(BaseTest):
+    "Base class for handler tests that write log files"
+
+    def setUp(self):
+        BaseTest.setUp(self)
+        self.fn = make_temp_file(".log", "test_logging-2-")
+        self.rmfiles = []
+
+    def tearDown(self):
+        for fn in self.rmfiles:
+            os.unlink(fn)
+        if os.path.exists(self.fn):
+            os.unlink(self.fn)
+        BaseTest.tearDown(self)
+
+    def assertLogFile(self, filename):
+        "Assert a log file is there and register it for deletion"
+        self.assertTrue(os.path.exists(filename),
+                        msg="Log file %r does not exist" % filename)
+        self.rmfiles.append(filename)
+
+    def next_rec(self):
+        return logging.LogRecord('n', logging.DEBUG, 'p', 1,
+                                 self.next_message(), None, None, None)
+
+class FileHandlerTest(BaseFileTest):
+    def test_delay(self):
+        os.unlink(self.fn)
+        fh = logging.FileHandler(self.fn, encoding='utf-8', delay=True)
+        self.assertIsNone(fh.stream)
+        self.assertFalse(os.path.exists(self.fn))
+        fh.handle(logging.makeLogRecord({}))
+        self.assertIsNotNone(fh.stream)
+        self.assertTrue(os.path.exists(self.fn))
+        fh.close()
+
+    def test_emit_after_closing_in_write_mode(self):
+        # Issue #42378
+        os.unlink(self.fn)
+        fh = logging.FileHandler(self.fn, encoding='utf-8', mode='w')
+        fh.setFormatter(logging.Formatter('%(message)s'))
+        fh.emit(self.next_rec())    # '1'
+        fh.close()
+        fh.emit(self.next_rec())    # '2'
+        with open(self.fn) as fp:
+            self.assertEqual(fp.read().strip(), '1')
+
+class RotatingFileHandlerTest(BaseFileTest):
+    def test_should_not_rollover(self):
+        # If file is empty rollover never occurs
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", maxBytes=1)
+        self.assertFalse(rh.shouldRollover(None))
+        rh.close()
+
+        # If maxBytes is zero rollover never occurs
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", maxBytes=0)
+        self.assertFalse(rh.shouldRollover(None))
+        rh.close()
+
+        with open(self.fn, 'wb') as f:
+            f.write(b'\n')
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", maxBytes=0)
+        self.assertFalse(rh.shouldRollover(None))
+        rh.close()
+
+    @unittest.skipIf(support.is_wasi, "WASI does not have /dev/null.")
+    def test_should_not_rollover_non_file(self):
+        # bpo-45401 - test with special file
+        # We set maxBytes to 1 so that rollover would normally happen, except
+        # for the check for regular files
+        rh = logging.handlers.RotatingFileHandler(
+            os.devnull, encoding="utf-8", maxBytes=1)
+        self.assertFalse(rh.shouldRollover(self.next_rec()))
+        rh.close()
+
+    def test_should_rollover(self):
+        with open(self.fn, 'wb') as f:
+            f.write(b'\n')
+        rh = logging.handlers.RotatingFileHandler(self.fn, encoding="utf-8", maxBytes=2)
+        self.assertTrue(rh.shouldRollover(self.next_rec()))
+        rh.close()
+
+    def test_file_created(self):
+        # checks that the file is created and assumes it was created
+        # by us
+        os.unlink(self.fn)
+        rh = logging.handlers.RotatingFileHandler(self.fn, encoding="utf-8")
+        rh.emit(self.next_rec())
+        self.assertLogFile(self.fn)
+        rh.close()
+
+    def test_max_bytes(self, delay=False):
+        kwargs = {'delay': delay} if delay else {}
+        os.unlink(self.fn)
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", backupCount=2, maxBytes=100, **kwargs)
+        self.assertIs(os.path.exists(self.fn), not delay)
+        small = logging.makeLogRecord({'msg': 'a'})
+        large = logging.makeLogRecord({'msg': 'b'*100})
+        self.assertFalse(rh.shouldRollover(small))
+        self.assertFalse(rh.shouldRollover(large))
+        rh.emit(small)
+        self.assertLogFile(self.fn)
+        self.assertFalse(os.path.exists(self.fn + ".1"))
+        self.assertFalse(rh.shouldRollover(small))
+        self.assertTrue(rh.shouldRollover(large))
+        rh.emit(large)
+        self.assertTrue(os.path.exists(self.fn))
+        self.assertLogFile(self.fn + ".1")
+        self.assertFalse(os.path.exists(self.fn + ".2"))
+        self.assertTrue(rh.shouldRollover(small))
+        self.assertTrue(rh.shouldRollover(large))
+        rh.close()
+
+    def test_max_bytes_delay(self):
+        self.test_max_bytes(delay=True)
+
+    def test_rollover_filenames(self):
+        def namer(name):
+            return name + ".test"
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", backupCount=2, maxBytes=1)
+        rh.namer = namer
+        rh.emit(self.next_rec())
+        self.assertLogFile(self.fn)
+        self.assertFalse(os.path.exists(namer(self.fn + ".1")))
+        rh.emit(self.next_rec())
+        self.assertLogFile(namer(self.fn + ".1"))
+        self.assertFalse(os.path.exists(namer(self.fn + ".2")))
+        rh.emit(self.next_rec())
+        self.assertLogFile(namer(self.fn + ".2"))
+        self.assertFalse(os.path.exists(namer(self.fn + ".3")))
+        rh.emit(self.next_rec())
+        self.assertFalse(os.path.exists(namer(self.fn + ".3")))
+        rh.close()
+
+    def test_namer_rotator_inheritance(self):
+        class HandlerWithNamerAndRotator(logging.handlers.RotatingFileHandler):
+            def namer(self, name):
+                return name + ".test"
+
+            def rotator(self, source, dest):
+                if os.path.exists(source):
+                    os.replace(source, dest + ".rotated")
+
+        rh = HandlerWithNamerAndRotator(
+            self.fn, encoding="utf-8", backupCount=2, maxBytes=1)
+        self.assertEqual(rh.namer(self.fn), self.fn + ".test")
+        rh.emit(self.next_rec())
+        self.assertLogFile(self.fn)
+        rh.emit(self.next_rec())
+        self.assertLogFile(rh.namer(self.fn + ".1") + ".rotated")
+        self.assertFalse(os.path.exists(rh.namer(self.fn + ".1")))
+        rh.close()
+
+    @support.requires_zlib()
+    def test_rotator(self):
+        def namer(name):
+            return name + ".gz"
+
+        def rotator(source, dest):
+            with open(source, "rb") as sf:
+                data = sf.read()
+                compressed = zlib.compress(data, 9)
+                with open(dest, "wb") as df:
+                    df.write(compressed)
+            os.remove(source)
+
+        rh = logging.handlers.RotatingFileHandler(
+            self.fn, encoding="utf-8", backupCount=2, maxBytes=1)
+        rh.rotator = rotator
+        rh.namer = namer
+        m1 = self.next_rec()
+        rh.emit(m1)
+        self.assertLogFile(self.fn)
+        m2 = self.next_rec()
+        rh.emit(m2)
+        fn = namer(self.fn + ".1")
+        self.assertLogFile(fn)
+        newline = os.linesep
+        with open(fn, "rb") as f:
+            compressed = f.read()
+            data = zlib.decompress(compressed)
+            self.assertEqual(data.decode("ascii"), m1.msg + newline)
+        rh.emit(self.next_rec())
+        fn = namer(self.fn + ".2")
+        self.assertLogFile(fn)
+        with open(fn, "rb") as f:
+            compressed = f.read()
+            data = zlib.decompress(compressed)
+            self.assertEqual(data.decode("ascii"), m1.msg + newline)
+        rh.emit(self.next_rec())
+        fn = namer(self.fn + ".2")
+        with open(fn, "rb") as f:
+            compressed = f.read()
+            data = zlib.decompress(compressed)
+            self.assertEqual(data.decode("ascii"), m2.msg + newline)
+        self.assertFalse(os.path.exists(namer(self.fn + ".3")))
+        rh.close()
+
+class TimedRotatingFileHandlerTest(BaseFileTest):
+    # TODO: RUSTPYTHON
+    @unittest.skip("OS dependent bug")
+    @unittest.skipIf(support.is_wasi, "WASI does not have /dev/null.")
+    def test_should_not_rollover(self):
+        # See bpo-45401. Should only ever rollover regular files
+        fh = logging.handlers.TimedRotatingFileHandler(
+            os.devnull, 'S', encoding="utf-8", backupCount=1)
+        time.sleep(1.1)    # a little over a second ...
+        r = logging.makeLogRecord({'msg': 'testing - device file'})
+        self.assertFalse(fh.shouldRollover(r))
+        fh.close()
+
+    # other test methods added below
+    def test_rollover(self):
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, 'S', encoding="utf-8", backupCount=1)
+        fmt = logging.Formatter('%(asctime)s %(message)s')
+        fh.setFormatter(fmt)
+        r1 = logging.makeLogRecord({'msg': 'testing - initial'})
+        fh.emit(r1)
+        self.assertLogFile(self.fn)
+        time.sleep(1.1)    # a little over a second ...
+        r2 = logging.makeLogRecord({'msg': 'testing - after delay'})
+        fh.emit(r2)
+        fh.close()
+        # At this point, we should have a recent rotated file which we
+        # can test for the existence of. However, in practice, on some
+        # machines which run really slowly, we don't know how far back
+        # in time to go to look for the log file. So, we go back a fair
+        # bit, and stop as soon as we see a rotated file. In theory this
+        # could of course still fail, but the chances are lower.
+        found = False
+        now = datetime.datetime.now()
+        GO_BACK = 5 * 60 # seconds
+        for secs in range(GO_BACK):
+            prev = now - datetime.timedelta(seconds=secs)
+            fn = self.fn + prev.strftime(".%Y-%m-%d_%H-%M-%S")
+            found = os.path.exists(fn)
+            if found:
+                self.rmfiles.append(fn)
+                break
+        msg = 'No rotated files found, went back %d seconds' % GO_BACK
+        if not found:
+            # print additional diagnostics
+            dn, fn = os.path.split(self.fn)
+            files = [f for f in os.listdir(dn) if f.startswith(fn)]
+            print('Test time: %s' % now.strftime("%Y-%m-%d %H-%M-%S"), file=sys.stderr)
+            print('The only matching files are: %s' % files, file=sys.stderr)
+            for f in files:
+                print('Contents of %s:' % f)
+                path = os.path.join(dn, f)
+                with open(path, 'r') as tf:
+                    print(tf.read())
+        self.assertTrue(found, msg=msg)
+
+    # TODO: RustPython
+    @unittest.skip("OS dependent bug")
+    def test_rollover_at_midnight(self, weekly=False):
+        os_helper.unlink(self.fn)
+        now = datetime.datetime.now()
+        atTime = now.time()
+        if not 0.1 < atTime.microsecond/1e6 < 0.9:
+            # The test requires all records to be emitted within
+            # the range of the same whole second.
+            time.sleep((0.1 - atTime.microsecond/1e6) % 1.0)
+            now = datetime.datetime.now()
+            atTime = now.time()
+        atTime = atTime.replace(microsecond=0)
+        fmt = logging.Formatter('%(asctime)s %(message)s')
+        when = f'W{now.weekday()}' if weekly else 'MIDNIGHT'
+        for i in range(3):
+            fh = logging.handlers.TimedRotatingFileHandler(
+                self.fn, encoding="utf-8", when=when, atTime=atTime)
+            fh.setFormatter(fmt)
+            r2 = logging.makeLogRecord({'msg': f'testing1 {i}'})
+            fh.emit(r2)
+            fh.close()
+        self.assertLogFile(self.fn)
+        with open(self.fn, encoding="utf-8") as f:
+            for i, line in enumerate(f):
+                self.assertIn(f'testing1 {i}', line)
+
+        os.utime(self.fn, (now.timestamp() - 1,)*2)
+        for i in range(2):
+            fh = logging.handlers.TimedRotatingFileHandler(
+                self.fn, encoding="utf-8", when=when, atTime=atTime)
+            fh.setFormatter(fmt)
+            r2 = logging.makeLogRecord({'msg': f'testing2 {i}'})
+            fh.emit(r2)
+            fh.close()
+        rolloverDate = now - datetime.timedelta(days=7 if weekly else 1)
+        otherfn = f'{self.fn}.{rolloverDate:%Y-%m-%d}'
+        self.assertLogFile(otherfn)
+        with open(self.fn, encoding="utf-8") as f:
+            for i, line in enumerate(f):
+                self.assertIn(f'testing2 {i}', line)
+        with open(otherfn, encoding="utf-8") as f:
+            for i, line in enumerate(f):
+                self.assertIn(f'testing1 {i}', line)
+
+    # TODO: RustPython
+    @unittest.skip("OS dependent bug")
+    def test_rollover_at_weekday(self):
+        self.test_rollover_at_midnight(weekly=True)
+
+    def test_invalid(self):
+        assertRaises = self.assertRaises
+        assertRaises(ValueError, logging.handlers.TimedRotatingFileHandler,
+                     self.fn, 'X', encoding="utf-8", delay=True)
+        assertRaises(ValueError, logging.handlers.TimedRotatingFileHandler,
+                     self.fn, 'W', encoding="utf-8", delay=True)
+        assertRaises(ValueError, logging.handlers.TimedRotatingFileHandler,
+                     self.fn, 'W7', encoding="utf-8", delay=True)
+
+    # TODO: Test for utc=False.
+    def test_compute_rollover_daily_attime(self):
+        currentTime = 0
+        rh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT',
+            utc=True, atTime=None)
+        try:
+            actual = rh.computeRollover(currentTime)
+            self.assertEqual(actual, currentTime + 24 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 24 * 60 * 60 - 1)
+            self.assertEqual(actual, currentTime + 24 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 24 * 60 * 60)
+            self.assertEqual(actual, currentTime + 48 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 25 * 60 * 60)
+            self.assertEqual(actual, currentTime + 48 * 60 * 60)
+        finally:
+            rh.close()
+
+        atTime = datetime.time(12, 0, 0)
+        rh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT',
+            utc=True, atTime=atTime)
+        try:
+            actual = rh.computeRollover(currentTime)
+            self.assertEqual(actual, currentTime + 12 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 12 * 60 * 60 - 1)
+            self.assertEqual(actual, currentTime + 12 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 12 * 60 * 60)
+            self.assertEqual(actual, currentTime + 36 * 60 * 60)
+
+            actual = rh.computeRollover(currentTime + 13 * 60 * 60)
+            self.assertEqual(actual, currentTime + 36 * 60 * 60)
+        finally:
+            rh.close()
+
+    # TODO: Test for utc=False.
+    def test_compute_rollover_weekly_attime(self):
+        currentTime = int(time.time())
+        today = currentTime - currentTime % 86400
+
+        atTime = datetime.time(12, 0, 0)
+
+        wday = time.gmtime(today).tm_wday
+        for day in range(7):
+            rh = logging.handlers.TimedRotatingFileHandler(
+                self.fn, encoding="utf-8", when='W%d' % day, interval=1, backupCount=0,
+                utc=True, atTime=atTime)
+            try:
+                if wday > day:
+                    # The rollover day has already passed this week, so we
+                    # go over into next week
+                    expected = (7 - wday + day)
+                else:
+                    expected = (day - wday)
+                # At this point expected is in days from now, convert to seconds
+                expected *= 24 * 60 * 60
+                # Add in the rollover time
+                expected += 12 * 60 * 60
+                # Add in adjustment for today
+                expected += today
+
+                actual = rh.computeRollover(today)
+                if actual != expected:
+                    print('failed in timezone: %d' % time.timezone)
+                    print('local vars: %s' % locals())
+                self.assertEqual(actual, expected)
+
+                actual = rh.computeRollover(today + 12 * 60 * 60 - 1)
+                if actual != expected:
+                    print('failed in timezone: %d' % time.timezone)
+                    print('local vars: %s' % locals())
+                self.assertEqual(actual, expected)
+
+                if day == wday:
+                    # goes into following week
+                    expected += 7 * 24 * 60 * 60
+                actual = rh.computeRollover(today + 12 * 60 * 60)
+                if actual != expected:
+                    print('failed in timezone: %d' % time.timezone)
+                    print('local vars: %s' % locals())
+                self.assertEqual(actual, expected)
+
+                actual = rh.computeRollover(today + 13 * 60 * 60)
+                if actual != expected:
+                    print('failed in timezone: %d' % time.timezone)
+                    print('local vars: %s' % locals())
+                self.assertEqual(actual, expected)
+            finally:
+                rh.close()
+
+    def test_compute_files_to_delete(self):
+        # See bpo-46063 for background
+        wd = tempfile.mkdtemp(prefix='test_logging_')
+        self.addCleanup(shutil.rmtree, wd)
+        times = []
+        dt = datetime.datetime.now()
+        for i in range(10):
+            times.append(dt.strftime('%Y-%m-%d_%H-%M-%S'))
+            dt += datetime.timedelta(seconds=5)
+        prefixes = ('a.b', 'a.b.c', 'd.e', 'd.e.f', 'g')
+        files = []
+        rotators = []
+        for prefix in prefixes:
+            p = os.path.join(wd, '%s.log' % prefix)
+            rotator = logging.handlers.TimedRotatingFileHandler(p, when='s',
+                                                                interval=5,
+                                                                backupCount=7,
+                                                                delay=True)
+            rotators.append(rotator)
+            if prefix.startswith('a.b'):
+                for t in times:
+                    files.append('%s.log.%s' % (prefix, t))
+            elif prefix.startswith('d.e'):
+                def namer(filename):
+                    dirname, basename = os.path.split(filename)
+                    basename = basename.replace('.log', '') + '.log'
+                    return os.path.join(dirname, basename)
+                rotator.namer = namer
+                for t in times:
+                    files.append('%s.%s.log' % (prefix, t))
+            elif prefix == 'g':
+                def namer(filename):
+                    dirname, basename = os.path.split(filename)
+                    basename = 'g' + basename[6:] + '.oldlog'
+                    return os.path.join(dirname, basename)
+                rotator.namer = namer
+                for t in times:
+                    files.append('g%s.oldlog' % t)
+        # Create empty files
+        for fn in files:
+            p = os.path.join(wd, fn)
+            with open(p, 'wb') as f:
+                pass
+        # Now the checks that only the correct files are offered up for deletion
+        for i, prefix in enumerate(prefixes):
+            rotator = rotators[i]
+            candidates = rotator.getFilesToDelete()
+            self.assertEqual(len(candidates), 3, candidates)
+            if prefix.startswith('a.b'):
+                p = '%s.log.' % prefix
+                for c in candidates:
+                    d, fn = os.path.split(c)
+                    self.assertTrue(fn.startswith(p))
+            elif prefix.startswith('d.e'):
+                for c in candidates:
+                    d, fn = os.path.split(c)
+                    self.assertTrue(fn.endswith('.log'), fn)
+                    self.assertTrue(fn.startswith(prefix + '.') and
+                                    fn[len(prefix) + 2].isdigit())
+            elif prefix == 'g':
+                for c in candidates:
+                    d, fn = os.path.split(c)
+                    self.assertTrue(fn.endswith('.oldlog'))
+                    self.assertTrue(fn.startswith('g') and fn[1].isdigit())
+
+    def test_compute_files_to_delete_same_filename_different_extensions(self):
+        # See GH-93205 for background
+        wd = pathlib.Path(tempfile.mkdtemp(prefix='test_logging_'))
+        self.addCleanup(shutil.rmtree, wd)
+        times = []
+        dt = datetime.datetime.now()
+        n_files = 10
+        for _ in range(n_files):
+            times.append(dt.strftime('%Y-%m-%d_%H-%M-%S'))
+            dt += datetime.timedelta(seconds=5)
+        prefixes = ('a.log', 'a.log.b')
+        files = []
+        rotators = []
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = logging.handlers.TimedRotatingFileHandler(wd / prefix, when='s',
+                                                                interval=5,
+                                                                backupCount=backupCount,
+                                                                delay=True)
+            rotators.append(rotator)
+            for t in times:
+                files.append('%s.%s' % (prefix, t))
+        for t in times:
+            files.append('a.log.%s.c' % t)
+        # Create empty files
+        for f in files:
+            (wd / f).touch()
+        # Now the checks that only the correct files are offered up for deletion
+        for i, prefix in enumerate(prefixes):
+            backupCount = i+1
+            rotator = rotators[i]
+            candidates = rotator.getFilesToDelete()
+            self.assertEqual(len(candidates), n_files - backupCount, candidates)
+            matcher = re.compile(r"^\d{4}-\d{2}-\d{2}_\d{2}-\d{2}-\d{2}\Z")
+            for c in candidates:
+                d, fn = os.path.split(c)
+                self.assertTrue(fn.startswith(prefix+'.'))
+                suffix = fn[(len(prefix)+1):]
+                self.assertRegex(suffix, matcher)
+
+    # Run with US-style DST rules: DST begins 2 a.m. on second Sunday in
+    # March (M3.2.0) and ends 2 a.m. on first Sunday in November (M11.1.0).
+    @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
+    def test_compute_rollover_MIDNIGHT_local(self):
+        # DST begins at 2012-3-11T02:00:00 and ends at 2012-11-4T02:00:00.
+        DT = datetime.datetime
+        def test(current, expected):
+            actual = fh.computeRollover(current.timestamp())
+            diff = actual - expected.timestamp()
+            if diff:
+                self.assertEqual(diff, 0, datetime.timedelta(seconds=diff))
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False)
+
+        test(DT(2012, 3, 10, 23, 59, 59), DT(2012, 3, 11, 0, 0))
+        test(DT(2012, 3, 11, 0, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 3, 11, 1, 0), DT(2012, 3, 12, 0, 0))
+
+        test(DT(2012, 11, 3, 23, 59, 59), DT(2012, 11, 4, 0, 0))
+        test(DT(2012, 11, 4, 0, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 5, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False,
+            atTime=datetime.time(12, 0, 0))
+
+        test(DT(2012, 3, 10, 11, 59, 59), DT(2012, 3, 10, 12, 0))
+        test(DT(2012, 3, 10, 12, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 3, 10, 13, 0), DT(2012, 3, 11, 12, 0))
+
+        test(DT(2012, 11, 3, 11, 59, 59), DT(2012, 11, 3, 12, 0))
+        test(DT(2012, 11, 3, 12, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 11, 3, 13, 0), DT(2012, 11, 4, 12, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False,
+            atTime=datetime.time(2, 0, 0))
+
+        test(DT(2012, 3, 10, 1, 59, 59), DT(2012, 3, 10, 2, 0))
+        # 2:00:00 is the same as 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 10, 2, 0), DT(2012, 3, 11, 3, 0))
+        test(DT(2012, 3, 10, 3, 0), DT(2012, 3, 11, 3, 0))
+
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 11, 3, 0))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 12, 2, 0))
+        test(DT(2012, 3, 11, 4, 0), DT(2012, 3, 12, 2, 0))
+
+        test(DT(2012, 11, 3, 1, 59, 59), DT(2012, 11, 3, 2, 0))
+        test(DT(2012, 11, 3, 2, 0), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 11, 3, 3, 0), DT(2012, 11, 4, 2, 0))
+
+        # 1:00:00-2:00:00 is repeated twice at 2012-11-4.
+        test(DT(2012, 11, 4, 1, 59, 59), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 11, 4, 1, 59, 59, fold=1), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 11, 4, 2, 0), DT(2012, 11, 5, 2, 0))
+        test(DT(2012, 11, 4, 3, 0), DT(2012, 11, 5, 2, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False,
+            atTime=datetime.time(2, 30, 0))
+
+        test(DT(2012, 3, 10, 2, 29, 59), DT(2012, 3, 10, 2, 30))
+        # No time 2:30:00 at 2012-3-11.
+        test(DT(2012, 3, 10, 2, 30), DT(2012, 3, 11, 3, 30))
+        test(DT(2012, 3, 10, 3, 0), DT(2012, 3, 11, 3, 30))
+
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 11, 3, 30))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 12, 2, 30))
+        test(DT(2012, 3, 11, 3, 30), DT(2012, 3, 12, 2, 30))
+
+        test(DT(2012, 11, 3, 2, 29, 59), DT(2012, 11, 3, 2, 30))
+        test(DT(2012, 11, 3, 2, 30), DT(2012, 11, 4, 2, 30))
+        test(DT(2012, 11, 3, 3, 0), DT(2012, 11, 4, 2, 30))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False,
+            atTime=datetime.time(1, 30, 0))
+
+        test(DT(2012, 3, 11, 1, 29, 59), DT(2012, 3, 11, 1, 30))
+        test(DT(2012, 3, 11, 1, 30), DT(2012, 3, 12, 1, 30))
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 12, 1, 30))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 12, 1, 30))
+        test(DT(2012, 3, 11, 3, 30), DT(2012, 3, 12, 1, 30))
+
+        # 1:00:00-2:00:00 is repeated twice at 2012-11-4.
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 4, 1, 30))
+        test(DT(2012, 11, 4, 1, 29, 59), DT(2012, 11, 4, 1, 30))
+        test(DT(2012, 11, 4, 1, 30), DT(2012, 11, 5, 1, 30))
+        test(DT(2012, 11, 4, 1, 59, 59), DT(2012, 11, 5, 1, 30))
+        # It is weird, but the rollover date jumps back from 2012-11-5
+        # to 2012-11-4.
+        test(DT(2012, 11, 4, 1, 0, fold=1), DT(2012, 11, 4, 1, 30, fold=1))
+        test(DT(2012, 11, 4, 1, 29, 59, fold=1), DT(2012, 11, 4, 1, 30, fold=1))
+        test(DT(2012, 11, 4, 1, 30, fold=1), DT(2012, 11, 5, 1, 30))
+        test(DT(2012, 11, 4, 1, 59, 59, fold=1), DT(2012, 11, 5, 1, 30))
+        test(DT(2012, 11, 4, 2, 0), DT(2012, 11, 5, 1, 30))
+        test(DT(2012, 11, 4, 2, 30), DT(2012, 11, 5, 1, 30))
+
+        fh.close()
+
+    # Run with US-style DST rules: DST begins 2 a.m. on second Sunday in
+    # March (M3.2.0) and ends 2 a.m. on first Sunday in November (M11.1.0).
+    @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
+    def test_compute_rollover_W6_local(self):
+        # DST begins at 2012-3-11T02:00:00 and ends at 2012-11-4T02:00:00.
+        DT = datetime.datetime
+        def test(current, expected):
+            actual = fh.computeRollover(current.timestamp())
+            diff = actual - expected.timestamp()
+            if diff:
+                self.assertEqual(diff, 0, datetime.timedelta(seconds=diff))
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False)
+
+        test(DT(2012, 3, 4, 23, 59, 59), DT(2012, 3, 5, 0, 0))
+        test(DT(2012, 3, 5, 0, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 3, 5, 1, 0), DT(2012, 3, 12, 0, 0))
+
+        test(DT(2012, 10, 28, 23, 59, 59), DT(2012, 10, 29, 0, 0))
+        test(DT(2012, 10, 29, 0, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 10, 29, 1, 0), DT(2012, 11, 5, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False,
+            atTime=datetime.time(0, 0, 0))
+
+        test(DT(2012, 3, 10, 23, 59, 59), DT(2012, 3, 11, 0, 0))
+        test(DT(2012, 3, 11, 0, 0), DT(2012, 3, 18, 0, 0))
+        test(DT(2012, 3, 11, 1, 0), DT(2012, 3, 18, 0, 0))
+
+        test(DT(2012, 11, 3, 23, 59, 59), DT(2012, 11, 4, 0, 0))
+        test(DT(2012, 11, 4, 0, 0), DT(2012, 11, 11, 0, 0))
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 11, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False,
+            atTime=datetime.time(12, 0, 0))
+
+        test(DT(2012, 3, 4, 11, 59, 59), DT(2012, 3, 4, 12, 0))
+        test(DT(2012, 3, 4, 12, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 3, 4, 13, 0), DT(2012, 3, 11, 12, 0))
+
+        test(DT(2012, 10, 28, 11, 59, 59), DT(2012, 10, 28, 12, 0))
+        test(DT(2012, 10, 28, 12, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 10, 28, 13, 0), DT(2012, 11, 4, 12, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False,
+            atTime=datetime.time(2, 0, 0))
+
+        test(DT(2012, 3, 4, 1, 59, 59), DT(2012, 3, 4, 2, 0))
+        # 2:00:00 is the same as 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 4, 2, 0), DT(2012, 3, 11, 3, 0))
+        test(DT(2012, 3, 4, 3, 0), DT(2012, 3, 11, 3, 0))
+
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 11, 3, 0))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 18, 2, 0))
+        test(DT(2012, 3, 11, 4, 0), DT(2012, 3, 18, 2, 0))
+
+        test(DT(2012, 10, 28, 1, 59, 59), DT(2012, 10, 28, 2, 0))
+        test(DT(2012, 10, 28, 2, 0), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 10, 28, 3, 0), DT(2012, 11, 4, 2, 0))
+
+        # 1:00:00-2:00:00 is repeated twice at 2012-11-4.
+        test(DT(2012, 11, 4, 1, 59, 59), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 11, 4, 1, 59, 59, fold=1), DT(2012, 11, 4, 2, 0))
+        test(DT(2012, 11, 4, 2, 0), DT(2012, 11, 11, 2, 0))
+        test(DT(2012, 11, 4, 3, 0), DT(2012, 11, 11, 2, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False,
+            atTime=datetime.time(2, 30, 0))
+
+        test(DT(2012, 3, 4, 2, 29, 59), DT(2012, 3, 4, 2, 30))
+        # No time 2:30:00 at 2012-3-11.
+        test(DT(2012, 3, 4, 2, 30), DT(2012, 3, 11, 3, 30))
+        test(DT(2012, 3, 4, 3, 0), DT(2012, 3, 11, 3, 30))
+
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 11, 3, 30))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 18, 2, 30))
+        test(DT(2012, 3, 11, 3, 30), DT(2012, 3, 18, 2, 30))
+
+        test(DT(2012, 10, 28, 2, 29, 59), DT(2012, 10, 28, 2, 30))
+        test(DT(2012, 10, 28, 2, 30), DT(2012, 11, 4, 2, 30))
+        test(DT(2012, 10, 28, 3, 0), DT(2012, 11, 4, 2, 30))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False,
+            atTime=datetime.time(1, 30, 0))
+
+        test(DT(2012, 3, 11, 1, 29, 59), DT(2012, 3, 11, 1, 30))
+        test(DT(2012, 3, 11, 1, 30), DT(2012, 3, 18, 1, 30))
+        test(DT(2012, 3, 11, 1, 59, 59), DT(2012, 3, 18, 1, 30))
+        # No time between 2:00:00 and 3:00:00 at 2012-3-11.
+        test(DT(2012, 3, 11, 3, 0), DT(2012, 3, 18, 1, 30))
+        test(DT(2012, 3, 11, 3, 30), DT(2012, 3, 18, 1, 30))
+
+        # 1:00:00-2:00:00 is repeated twice at 2012-11-4.
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 4, 1, 30))
+        test(DT(2012, 11, 4, 1, 29, 59), DT(2012, 11, 4, 1, 30))
+        test(DT(2012, 11, 4, 1, 30), DT(2012, 11, 11, 1, 30))
+        test(DT(2012, 11, 4, 1, 59, 59), DT(2012, 11, 11, 1, 30))
+        # It is weird, but the rollover date jumps back from 2012-11-11
+        # to 2012-11-4.
+        test(DT(2012, 11, 4, 1, 0, fold=1), DT(2012, 11, 4, 1, 30, fold=1))
+        test(DT(2012, 11, 4, 1, 29, 59, fold=1), DT(2012, 11, 4, 1, 30, fold=1))
+        test(DT(2012, 11, 4, 1, 30, fold=1), DT(2012, 11, 11, 1, 30))
+        test(DT(2012, 11, 4, 1, 59, 59, fold=1), DT(2012, 11, 11, 1, 30))
+        test(DT(2012, 11, 4, 2, 0), DT(2012, 11, 11, 1, 30))
+        test(DT(2012, 11, 4, 2, 30), DT(2012, 11, 11, 1, 30))
+
+        fh.close()
+
+    # Run with US-style DST rules: DST begins 2 a.m. on second Sunday in
+    # March (M3.2.0) and ends 2 a.m. on first Sunday in November (M11.1.0).
+    @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
+    def test_compute_rollover_MIDNIGHT_local_interval(self):
+        # DST begins at 2012-3-11T02:00:00 and ends at 2012-11-4T02:00:00.
+        DT = datetime.datetime
+        def test(current, expected):
+            actual = fh.computeRollover(current.timestamp())
+            diff = actual - expected.timestamp()
+            if diff:
+                self.assertEqual(diff, 0, datetime.timedelta(seconds=diff))
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False, interval=3)
+
+        test(DT(2012, 3, 8, 23, 59, 59), DT(2012, 3, 11, 0, 0))
+        test(DT(2012, 3, 9, 0, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 3, 9, 1, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 3, 10, 23, 59, 59), DT(2012, 3, 13, 0, 0))
+        test(DT(2012, 3, 11, 0, 0), DT(2012, 3, 14, 0, 0))
+        test(DT(2012, 3, 11, 1, 0), DT(2012, 3, 14, 0, 0))
+
+        test(DT(2012, 11, 1, 23, 59, 59), DT(2012, 11, 4, 0, 0))
+        test(DT(2012, 11, 2, 0, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 11, 2, 1, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 11, 3, 23, 59, 59), DT(2012, 11, 6, 0, 0))
+        test(DT(2012, 11, 4, 0, 0), DT(2012, 11, 7, 0, 0))
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 7, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='MIDNIGHT', utc=False, interval=3,
+            atTime=datetime.time(12, 0, 0))
+
+        test(DT(2012, 3, 8, 11, 59, 59), DT(2012, 3, 10, 12, 0))
+        test(DT(2012, 3, 8, 12, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 3, 8, 13, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 3, 10, 11, 59, 59), DT(2012, 3, 12, 12, 0))
+        test(DT(2012, 3, 10, 12, 0), DT(2012, 3, 13, 12, 0))
+        test(DT(2012, 3, 10, 13, 0), DT(2012, 3, 13, 12, 0))
+
+        test(DT(2012, 11, 1, 11, 59, 59), DT(2012, 11, 3, 12, 0))
+        test(DT(2012, 11, 1, 12, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 11, 1, 13, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 11, 3, 11, 59, 59), DT(2012, 11, 5, 12, 0))
+        test(DT(2012, 11, 3, 12, 0), DT(2012, 11, 6, 12, 0))
+        test(DT(2012, 11, 3, 13, 0), DT(2012, 11, 6, 12, 0))
+
+        fh.close()
+
+    # Run with US-style DST rules: DST begins 2 a.m. on second Sunday in
+    # March (M3.2.0) and ends 2 a.m. on first Sunday in November (M11.1.0).
+    @support.run_with_tz('EST+05EDT,M3.2.0,M11.1.0')
+    def test_compute_rollover_W6_local_interval(self):
+        # DST begins at 2012-3-11T02:00:00 and ends at 2012-11-4T02:00:00.
+        DT = datetime.datetime
+        def test(current, expected):
+            actual = fh.computeRollover(current.timestamp())
+            diff = actual - expected.timestamp()
+            if diff:
+                self.assertEqual(diff, 0, datetime.timedelta(seconds=diff))
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False, interval=3)
+
+        test(DT(2012, 2, 19, 23, 59, 59), DT(2012, 3, 5, 0, 0))
+        test(DT(2012, 2, 20, 0, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 2, 20, 1, 0), DT(2012, 3, 12, 0, 0))
+        test(DT(2012, 3, 4, 23, 59, 59), DT(2012, 3, 19, 0, 0))
+        test(DT(2012, 3, 5, 0, 0), DT(2012, 3, 26, 0, 0))
+        test(DT(2012, 3, 5, 1, 0), DT(2012, 3, 26, 0, 0))
+
+        test(DT(2012, 10, 14, 23, 59, 59), DT(2012, 10, 29, 0, 0))
+        test(DT(2012, 10, 15, 0, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 10, 15, 1, 0), DT(2012, 11, 5, 0, 0))
+        test(DT(2012, 10, 28, 23, 59, 59), DT(2012, 11, 12, 0, 0))
+        test(DT(2012, 10, 29, 0, 0), DT(2012, 11, 19, 0, 0))
+        test(DT(2012, 10, 29, 1, 0), DT(2012, 11, 19, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False, interval=3,
+            atTime=datetime.time(0, 0, 0))
+
+        test(DT(2012, 2, 25, 23, 59, 59), DT(2012, 3, 11, 0, 0))
+        test(DT(2012, 2, 26, 0, 0), DT(2012, 3, 18, 0, 0))
+        test(DT(2012, 2, 26, 1, 0), DT(2012, 3, 18, 0, 0))
+        test(DT(2012, 3, 10, 23, 59, 59), DT(2012, 3, 25, 0, 0))
+        test(DT(2012, 3, 11, 0, 0), DT(2012, 4, 1, 0, 0))
+        test(DT(2012, 3, 11, 1, 0), DT(2012, 4, 1, 0, 0))
+
+        test(DT(2012, 10, 20, 23, 59, 59), DT(2012, 11, 4, 0, 0))
+        test(DT(2012, 10, 21, 0, 0), DT(2012, 11, 11, 0, 0))
+        test(DT(2012, 10, 21, 1, 0), DT(2012, 11, 11, 0, 0))
+        test(DT(2012, 11, 3, 23, 59, 59), DT(2012, 11, 18, 0, 0))
+        test(DT(2012, 11, 4, 0, 0), DT(2012, 11, 25, 0, 0))
+        test(DT(2012, 11, 4, 1, 0), DT(2012, 11, 25, 0, 0))
+
+        fh.close()
+
+        fh = logging.handlers.TimedRotatingFileHandler(
+            self.fn, encoding="utf-8", when='W6', utc=False, interval=3,
+            atTime=datetime.time(12, 0, 0))
+
+        test(DT(2012, 2, 18, 11, 59, 59), DT(2012, 3, 4, 12, 0))
+        test(DT(2012, 2, 19, 12, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 2, 19, 13, 0), DT(2012, 3, 11, 12, 0))
+        test(DT(2012, 3, 4, 11, 59, 59), DT(2012, 3, 18, 12, 0))
+        test(DT(2012, 3, 4, 12, 0), DT(2012, 3, 25, 12, 0))
+        test(DT(2012, 3, 4, 13, 0), DT(2012, 3, 25, 12, 0))
+
+        test(DT(2012, 10, 14, 11, 59, 59), DT(2012, 10, 28, 12, 0))
+        test(DT(2012, 10, 14, 12, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 10, 14, 13, 0), DT(2012, 11, 4, 12, 0))
+        test(DT(2012, 10, 28, 11, 59, 59), DT(2012, 11, 11, 12, 0))
+        test(DT(2012, 10, 28, 12, 0), DT(2012, 11, 18, 12, 0))
+        test(DT(2012, 10, 28, 13, 0), DT(2012, 11, 18, 12, 0))
+
+        fh.close()
+
+
+def secs(**kw):
+    return datetime.timedelta(**kw) // datetime.timedelta(seconds=1)
+
+for when, exp in (('S', 1),
+                  ('M', 60),
+                  ('H', 60 * 60),
+                  ('D', 60 * 60 * 24),
+                  ('MIDNIGHT', 60 * 60 * 24),
+                  # current time (epoch start) is a Thursday, W0 means Monday
+                  ('W0', secs(days=4, hours=24)),
+                  ):
+    for interval in 1, 3:
+        def test_compute_rollover(self, when=when, interval=interval, exp=exp):
+            rh = logging.handlers.TimedRotatingFileHandler(
+                self.fn, encoding="utf-8", when=when, interval=interval, backupCount=0, utc=True)
+            currentTime = 0.0
+            actual = rh.computeRollover(currentTime)
+            if when.startswith('W'):
+                exp += secs(days=7*(interval-1))
+            else:
+                exp *= interval
+            if exp != actual:
+                # Failures occur on some systems for MIDNIGHT and W0.
+                # Print detailed calculation for MIDNIGHT so we can try to see
+                # what's going on
+                if when == 'MIDNIGHT':
+                    try:
+                        if rh.utc:
+                            t = time.gmtime(currentTime)
+                        else:
+                            t = time.localtime(currentTime)
+                        currentHour = t[3]
+                        currentMinute = t[4]
+                        currentSecond = t[5]
+                        # r is the number of seconds left between now and midnight
+                        r = logging.handlers._MIDNIGHT - ((currentHour * 60 +
+                                                           currentMinute) * 60 +
+                                                          currentSecond)
+                        result = currentTime + r
+                        print('t: %s (%s)' % (t, rh.utc), file=sys.stderr)
+                        print('currentHour: %s' % currentHour, file=sys.stderr)
+                        print('currentMinute: %s' % currentMinute, file=sys.stderr)
+                        print('currentSecond: %s' % currentSecond, file=sys.stderr)
+                        print('r: %s' % r, file=sys.stderr)
+                        print('result: %s' % result, file=sys.stderr)
+                    except Exception as e:
+                        print('exception in diagnostic code: %s' % e, file=sys.stderr)
+            self.assertEqual(exp, actual)
+            rh.close()
+        name = "test_compute_rollover_%s" % when
+        if interval > 1:
+            name += "_interval"
+        test_compute_rollover.__name__ = name
+        setattr(TimedRotatingFileHandlerTest, name, test_compute_rollover)
+
+
+@unittest.skipUnless(win32evtlog, 'win32evtlog/win32evtlogutil/pywintypes required for this test.')
+class NTEventLogHandlerTest(BaseTest):
+    def test_basic(self):
+        logtype = 'Application'
+        elh = win32evtlog.OpenEventLog(None, logtype)
+        num_recs = win32evtlog.GetNumberOfEventLogRecords(elh)
+
+        try:
+            h = logging.handlers.NTEventLogHandler('test_logging')
+        except pywintypes.error as e:
+            if e.winerror == 5:  # access denied
+                raise unittest.SkipTest('Insufficient privileges to run test')
+            raise
+
+        r = logging.makeLogRecord({'msg': 'Test Log Message'})
+        h.handle(r)
+        h.close()
+        # Now see if the event is recorded
+        self.assertLess(num_recs, win32evtlog.GetNumberOfEventLogRecords(elh))
+        flags = win32evtlog.EVENTLOG_BACKWARDS_READ | \
+                win32evtlog.EVENTLOG_SEQUENTIAL_READ
+        found = False
+        GO_BACK = 100
+        events = win32evtlog.ReadEventLog(elh, flags, GO_BACK)
+        for e in events:
+            if e.SourceName != 'test_logging':
+                continue
+            msg = win32evtlogutil.SafeFormatMessage(e, logtype)
+            if msg != 'Test Log Message\r\n':
+                continue
+            found = True
+            break
+        msg = 'Record not found in event log, went back %d records' % GO_BACK
+        self.assertTrue(found, msg=msg)
+
+
+class MiscTestCase(unittest.TestCase):
+    def test__all__(self):
+        not_exported = {
+            'logThreads', 'logMultiprocessing', 'logProcesses', 'currentframe',
+            'PercentStyle', 'StrFormatStyle', 'StringTemplateStyle',
+            'Filterer', 'PlaceHolder', 'Manager', 'RootLogger', 'root',
+            'threading', 'logAsyncioTasks'}
+        support.check__all__(self, logging, not_exported=not_exported)
+
+
+# Set the locale to the platform-dependent default.  I have no idea
+# why the test does this, but in any case we save the current locale
+# first and restore it at the end.
+def setUpModule():
+    unittest.enterModuleContext(support.run_with_locale('LC_ALL', ''))
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/Lib/test/test_math.py b/Lib/test/test_math.py
index 2f64180652..fa79456ed4 100644
--- a/Lib/test/test_math.py
+++ b/Lib/test/test_math.py
@@ -4,6 +4,7 @@
 from test.support import verbose, requires_IEEE_754
 from test import support
 import unittest
+import fractions
 import itertools
 import decimal
 import math
@@ -186,6 +187,9 @@ def result_check(expected, got, ulp_tol=5, abs_tol=0.0):
 
     # Check exactly equal (applies also to strings representing exceptions)
     if got == expected:
+        if not got and not expected:
+            if math.copysign(1, got) != math.copysign(1, expected):
+                return f"expected {expected}, got {got} (zero has wrong sign)"
         return None
 
     failure = "not equal"
@@ -234,6 +238,10 @@ def __init__(self, value):
     def __index__(self):
         return self.value
 
+class BadDescr:
+    def __get__(self, obj, objtype=None):
+        raise ValueError
+
 class MathTests(unittest.TestCase):
 
     def ftest(self, name, got, expected, ulp_tol=5, abs_tol=0.0):
@@ -323,6 +331,7 @@ def testAtan2(self):
         self.ftest('atan2(0, 1)', math.atan2(0, 1), 0)
         self.ftest('atan2(1, 1)', math.atan2(1, 1), math.pi/4)
         self.ftest('atan2(1, 0)', math.atan2(1, 0), math.pi/2)
+        self.ftest('atan2(1, -1)', math.atan2(1, -1), 3*math.pi/4)
 
         # math.atan2(0, x)
         self.ftest('atan2(0., -inf)', math.atan2(0., NINF), math.pi)
@@ -416,16 +425,22 @@ def __ceil__(self):
                 return 42
         class TestNoCeil:
             pass
+        class TestBadCeil:
+            __ceil__ = BadDescr()
         self.assertEqual(math.ceil(TestCeil()), 42)
         self.assertEqual(math.ceil(FloatCeil()), 42)
         self.assertEqual(math.ceil(FloatLike(42.5)), 43)
         self.assertRaises(TypeError, math.ceil, TestNoCeil())
+        self.assertRaises(ValueError, math.ceil, TestBadCeil())
 
         t = TestNoCeil()
         t.__ceil__ = lambda *args: args
         self.assertRaises(TypeError, math.ceil, t)
         self.assertRaises(TypeError, math.ceil, t, 0)
 
+        self.assertEqual(math.ceil(FloatLike(+1.0)), +1.0)
+        self.assertEqual(math.ceil(FloatLike(-1.0)), -1.0)
+
     @requires_IEEE_754
     def testCopysign(self):
         self.assertEqual(math.copysign(1, 42), 1.0)
@@ -566,16 +581,22 @@ def __floor__(self):
                 return 42
         class TestNoFloor:
             pass
+        class TestBadFloor:
+            __floor__ = BadDescr()
         self.assertEqual(math.floor(TestFloor()), 42)
         self.assertEqual(math.floor(FloatFloor()), 42)
         self.assertEqual(math.floor(FloatLike(41.9)), 41)
         self.assertRaises(TypeError, math.floor, TestNoFloor())
+        self.assertRaises(ValueError, math.floor, TestBadFloor())
 
         t = TestNoFloor()
         t.__floor__ = lambda *args: args
         self.assertRaises(TypeError, math.floor, t)
         self.assertRaises(TypeError, math.floor, t, 0)
 
+        self.assertEqual(math.floor(FloatLike(+1.0)), +1.0)
+        self.assertEqual(math.floor(FloatLike(-1.0)), -1.0)
+
     def testFmod(self):
         self.assertRaises(TypeError, math.fmod)
         self.ftest('fmod(10, 1)', math.fmod(10, 1), 0.0)
@@ -597,6 +618,7 @@ def testFmod(self):
         self.assertEqual(math.fmod(-3.0, NINF), -3.0)
         self.assertEqual(math.fmod(0.0, 3.0), 0.0)
         self.assertEqual(math.fmod(0.0, NINF), 0.0)
+        self.assertRaises(ValueError, math.fmod, INF, INF)
 
     def testFrexp(self):
         self.assertRaises(TypeError, math.frexp)
@@ -638,7 +660,7 @@ def testFsum(self):
         def msum(iterable):
             """Full precision summation.  Compute sum(iterable) without any
             intermediate accumulation of error.  Based on the 'lsum' function
-            at http://code.activestate.com/recipes/393090/
+            at https://code.activestate.com/recipes/393090-binary-floating-point-summation-accurate-to-full-p/
 
             """
             tmant, texp = 0, 0
@@ -666,6 +688,7 @@ def msum(iterable):
             ([], 0.0),
             ([0.0], 0.0),
             ([1e100, 1.0, -1e100, 1e-100, 1e50, -1.0, -1e50], 1e-100),
+            ([1e100, 1.0, -1e100, 1e-100, 1e50, -1, -1e50], 1e-100),
             ([2.0**53, -0.5, -2.0**-54], 2.0**53-1.0),
             ([2.0**53, 1.0, 2.0**-100], 2.0**53+2.0),
             ([2.0**53+10.0, 1.0, 2.0**-100], 2.0**53+12.0),
@@ -713,6 +736,22 @@ def msum(iterable):
             s = msum(vals)
             self.assertEqual(msum(vals), math.fsum(vals))
 
+        self.assertEqual(math.fsum([1.0, math.inf]), math.inf)
+        self.assertTrue(math.isnan(math.fsum([math.nan, 1.0])))
+        self.assertEqual(math.fsum([1e100, FloatLike(1.0), -1e100, 1e-100,
+                                    1e50, FloatLike(-1.0), -1e50]), 1e-100)
+        self.assertRaises(OverflowError, math.fsum, [1e+308, 1e+308])
+        self.assertRaises(ValueError, math.fsum, [math.inf, -math.inf])
+        self.assertRaises(TypeError, math.fsum, ['spam'])
+        self.assertRaises(TypeError, math.fsum, 1)
+        self.assertRaises(OverflowError, math.fsum, [10**1000])
+
+        def bad_iter():
+            yield 1.0
+            raise ZeroDivisionError
+
+        self.assertRaises(ZeroDivisionError, math.fsum, bad_iter())
+
     def testGcd(self):
         gcd = math.gcd
         self.assertEqual(gcd(0, 0), 0)
@@ -773,9 +812,13 @@ def testHypot(self):
         # Test allowable types (those with __float__)
         self.assertEqual(hypot(12.0, 5.0), 13.0)
         self.assertEqual(hypot(12, 5), 13)
+        self.assertEqual(hypot(0.75, -1), 1.25)
+        self.assertEqual(hypot(-1, 0.75), 1.25)
+        self.assertEqual(hypot(0.75, FloatLike(-1.)), 1.25)
+        self.assertEqual(hypot(FloatLike(-1.), 0.75), 1.25)
         self.assertEqual(hypot(Decimal(12), Decimal(5)), 13)
         self.assertEqual(hypot(Fraction(12, 32), Fraction(5, 32)), Fraction(13, 32))
-        self.assertEqual(hypot(bool(1), bool(0), bool(1), bool(1)), math.sqrt(3))
+        self.assertEqual(hypot(True, False, True, True, True), 2.0)
 
         # Test corner cases
         self.assertEqual(hypot(0.0, 0.0), 0.0)     # Max input is zero
@@ -830,6 +873,8 @@ def testHypot(self):
             scale = FLOAT_MIN / 2.0 ** exp
             self.assertEqual(math.hypot(4*scale, 3*scale), 5*scale)
 
+        self.assertRaises(TypeError, math.hypot, *([1.0]*18), 'spam')
+
     @requires_IEEE_754
     @unittest.skipIf(HAVE_DOUBLE_ROUNDING,
                      "hypot() loses accuracy on machines with double rounding")
@@ -922,12 +967,16 @@ def testDist(self):
         # Test allowable types (those with __float__)
         self.assertEqual(dist((14.0, 1.0), (2.0, -4.0)), 13.0)
         self.assertEqual(dist((14, 1), (2, -4)), 13)
+        self.assertEqual(dist((FloatLike(14.), 1), (2, -4)), 13)
+        self.assertEqual(dist((11, 1), (FloatLike(-1.), -4)), 13)
+        self.assertEqual(dist((14, FloatLike(-1.)), (2, -6)), 13)
+        self.assertEqual(dist((14, -1), (2, -6)), 13)
         self.assertEqual(dist((D(14), D(1)), (D(2), D(-4))), D(13))
         self.assertEqual(dist((F(14, 32), F(1, 32)), (F(2, 32), F(-4, 32))),
                          F(13, 32))
-        self.assertEqual(dist((True, True, False, True, False),
-                              (True, False, True, True, False)),
-                         sqrt(2.0))
+        self.assertEqual(dist((True, True, False, False, True, True),
+                              (True, False, True, False, False, False)),
+                         2.0)
 
         # Test corner cases
         self.assertEqual(dist((13.25, 12.5, -3.25),
@@ -965,6 +1014,8 @@ class T(tuple):
             dist((1, 2, 3, 4), (5, 6, 7))
         with self.assertRaises(ValueError):        # Check dimension agree
             dist((1, 2, 3), (4, 5, 6, 7))
+        with self.assertRaises(TypeError):
+            dist((1,)*17 + ("spam",), (1,)*18)
         with self.assertRaises(TypeError):         # Rejects invalid types
             dist("abc", "xyz")
         int_too_big_for_float = 10 ** (sys.float_info.max_10_exp + 5)
@@ -972,6 +1023,16 @@ class T(tuple):
             dist((1, int_too_big_for_float), (2, 3))
         with self.assertRaises((ValueError, OverflowError)):
             dist((2, 3), (1, int_too_big_for_float))
+        with self.assertRaises(TypeError):
+            dist((1,), 2)
+        with self.assertRaises(TypeError):
+            dist([1], 2)
+
+        class BadFloat:
+            __float__ = BadDescr()
+
+        with self.assertRaises(ValueError):
+            dist([1], [BadFloat()])
 
         # Verify that the one dimensional case is equivalent to abs()
         for i in range(20):
@@ -1110,6 +1171,7 @@ def test_lcm(self):
 
     def testLdexp(self):
         self.assertRaises(TypeError, math.ldexp)
+        self.assertRaises(TypeError, math.ldexp, 2.0, 1.1)
         self.ftest('ldexp(0,1)', math.ldexp(0,1), 0)
         self.ftest('ldexp(1,1)', math.ldexp(1,1), 2)
         self.ftest('ldexp(1,-1)', math.ldexp(1,-1), 0.5)
@@ -1142,6 +1204,7 @@ def testLdexp(self):
 
     def testLog(self):
         self.assertRaises(TypeError, math.log)
+        self.assertRaises(TypeError, math.log, 1, 2, 3)
         self.ftest('log(1/e)', math.log(1/math.e), -1)
         self.ftest('log(1)', math.log(1), 0)
         self.ftest('log(e)', math.log(math.e), 1)
@@ -1152,6 +1215,7 @@ def testLog(self):
                    2302.5850929940457)
         self.assertRaises(ValueError, math.log, -1.5)
         self.assertRaises(ValueError, math.log, -10**1000)
+        self.assertRaises(ValueError, math.log, 10, -10)
         self.assertRaises(ValueError, math.log, NINF)
         self.assertEqual(math.log(INF), INF)
         self.assertTrue(math.isnan(math.log(NAN)))
@@ -1202,6 +1266,277 @@ def testLog10(self):
         self.assertEqual(math.log(INF), INF)
         self.assertTrue(math.isnan(math.log10(NAN)))
 
+    def testSumProd(self):
+        sumprod = math.sumprod
+        Decimal = decimal.Decimal
+        Fraction = fractions.Fraction
+
+        # Core functionality
+        self.assertEqual(sumprod(iter([10, 20, 30]), (1, 2, 3)), 140)
+        self.assertEqual(sumprod([1.5, 2.5], [3.5, 4.5]), 16.5)
+        self.assertEqual(sumprod([], []), 0)
+        self.assertEqual(sumprod([-1], [1.]), -1)
+        self.assertEqual(sumprod([1.], [-1]), -1)
+
+        # Type preservation and coercion
+        for v in [
+            (10, 20, 30),
+            (1.5, -2.5),
+            (Fraction(3, 5), Fraction(4, 5)),
+            (Decimal(3.5), Decimal(4.5)),
+            (2.5, 10),             # float/int
+            (2.5, Fraction(3, 5)), # float/fraction
+            (25, Fraction(3, 5)),  # int/fraction
+            (25, Decimal(4.5)),    # int/decimal
+        ]:
+            for p, q in [(v, v), (v, v[::-1])]:
+                with self.subTest(p=p, q=q):
+                    expected = sum(p_i * q_i for p_i, q_i in zip(p, q, strict=True))
+                    actual = sumprod(p, q)
+                    self.assertEqual(expected, actual)
+                    self.assertEqual(type(expected), type(actual))
+
+        # Bad arguments
+        self.assertRaises(TypeError, sumprod)               # No args
+        self.assertRaises(TypeError, sumprod, [])           # One arg
+        self.assertRaises(TypeError, sumprod, [], [], [])   # Three args
+        self.assertRaises(TypeError, sumprod, None, [10])   # Non-iterable
+        self.assertRaises(TypeError, sumprod, [10], None)   # Non-iterable
+        self.assertRaises(TypeError, sumprod, ['x'], [1.0])
+
+        # Uneven lengths
+        self.assertRaises(ValueError, sumprod, [10, 20], [30])
+        self.assertRaises(ValueError, sumprod, [10], [20, 30])
+
+        # Overflows
+        self.assertEqual(sumprod([10**20], [1]), 10**20)
+        self.assertEqual(sumprod([1], [10**20]), 10**20)
+        self.assertEqual(sumprod([10**10], [10**10]), 10**20)
+        self.assertEqual(sumprod([10**7]*10**5, [10**7]*10**5), 10**19)
+        self.assertRaises(OverflowError, sumprod, [10**1000], [1.0])
+        self.assertRaises(OverflowError, sumprod, [1.0], [10**1000])
+
+        # Error in iterator
+        def raise_after(n):
+            for i in range(n):
+                yield i
+            raise RuntimeError
+        with self.assertRaises(RuntimeError):
+            sumprod(range(10), raise_after(5))
+        with self.assertRaises(RuntimeError):
+            sumprod(raise_after(5), range(10))
+
+        from test.test_iter import BasicIterClass
+
+        self.assertEqual(sumprod(BasicIterClass(1), [1]), 0)
+        self.assertEqual(sumprod([1], BasicIterClass(1)), 0)
+
+        # Error in multiplication
+        class BadMultiply:
+            def __mul__(self, other):
+                raise RuntimeError
+            def __rmul__(self, other):
+                raise RuntimeError
+        with self.assertRaises(RuntimeError):
+            sumprod([10, BadMultiply(), 30], [1, 2, 3])
+        with self.assertRaises(RuntimeError):
+            sumprod([1, 2, 3], [10, BadMultiply(), 30])
+
+        # Error in addition
+        with self.assertRaises(TypeError):
+            sumprod(['abc', 3], [5, 10])
+        with self.assertRaises(TypeError):
+            sumprod([5, 10], ['abc', 3])
+
+        # Special values should give the same as the pure python recipe
+        self.assertEqual(sumprod([10.1, math.inf], [20.2, 30.3]), math.inf)
+        self.assertEqual(sumprod([10.1, math.inf], [math.inf, 30.3]), math.inf)
+        self.assertEqual(sumprod([10.1, math.inf], [math.inf, math.inf]), math.inf)
+        self.assertEqual(sumprod([10.1, -math.inf], [20.2, 30.3]), -math.inf)
+        self.assertTrue(math.isnan(sumprod([10.1, math.inf], [-math.inf, math.inf])))
+        self.assertTrue(math.isnan(sumprod([10.1, math.nan], [20.2, 30.3])))
+        self.assertTrue(math.isnan(sumprod([10.1, math.inf], [math.nan, 30.3])))
+        self.assertTrue(math.isnan(sumprod([10.1, math.inf], [20.3, math.nan])))
+
+        # Error cases that arose during development
+        args = ((-5, -5, 10), (1.5, 4611686018427387904, 2305843009213693952))
+        self.assertEqual(sumprod(*args), 0.0)
+
+
+    @requires_IEEE_754
+    @unittest.skipIf(HAVE_DOUBLE_ROUNDING,
+                         "sumprod() accuracy not guaranteed on machines with double rounding")
+    @support.cpython_only    # Other implementations may choose a different algorithm
+    def test_sumprod_accuracy(self):
+        sumprod = math.sumprod
+        self.assertEqual(sumprod([0.1] * 10, [1]*10), 1.0)
+        self.assertEqual(sumprod([0.1] * 20, [True, False] * 10), 1.0)
+        self.assertEqual(sumprod([True, False] * 10, [0.1] * 20), 1.0)
+        self.assertEqual(sumprod([1.0, 10E100, 1.0, -10E100], [1.0]*4), 2.0)
+
+    @support.requires_resource('cpu')
+    def test_sumprod_stress(self):
+        sumprod = math.sumprod
+        product = itertools.product
+        Decimal = decimal.Decimal
+        Fraction = fractions.Fraction
+
+        class Int(int):
+            def __add__(self, other):
+                return Int(int(self) + int(other))
+            def __mul__(self, other):
+                return Int(int(self) * int(other))
+            __radd__ = __add__
+            __rmul__ = __mul__
+            def __repr__(self):
+                return f'Int({int(self)})'
+
+        class Flt(float):
+            def __add__(self, other):
+                return Int(int(self) + int(other))
+            def __mul__(self, other):
+                return Int(int(self) * int(other))
+            __radd__ = __add__
+            __rmul__ = __mul__
+            def __repr__(self):
+                return f'Flt({int(self)})'
+
+        def baseline_sumprod(p, q):
+            """This defines the target behavior including exceptions and special values.
+            However, it is subject to rounding errors, so float inputs should be exactly
+            representable with only a few bits.
+            """
+            total = 0
+            for p_i, q_i in zip(p, q, strict=True):
+                total += p_i * q_i
+            return total
+
+        def run(func, *args):
+            "Make comparing functions easier. Returns error status, type, and result."
+            try:
+                result = func(*args)
+            except (AssertionError, NameError):
+                raise
+            except Exception as e:
+                return type(e), None, 'None'
+            return None, type(result), repr(result)
+
+        pools = [
+            (-5, 10, -2**20, 2**31, 2**40, 2**61, 2**62, 2**80, 1.5, Int(7)),
+            (5.25, -3.5, 4.75, 11.25, 400.5, 0.046875, 0.25, -1.0, -0.078125),
+            (-19.0*2**500, 11*2**1000, -3*2**1500, 17*2*333,
+               5.25, -3.25, -3.0*2**(-333),  3, 2**513),
+            (3.75, 2.5, -1.5, float('inf'), -float('inf'), float('NaN'), 14,
+                9, 3+4j, Flt(13), 0.0),
+            (13.25, -4.25, Decimal('10.5'), Decimal('-2.25'), Fraction(13, 8),
+                 Fraction(-11, 16), 4.75 + 0.125j, 97, -41, Int(3)),
+            (Decimal('6.125'), Decimal('12.375'), Decimal('-2.75'), Decimal(0),
+                 Decimal('Inf'), -Decimal('Inf'), Decimal('NaN'), 12, 13.5),
+            (-2.0 ** -1000, 11*2**1000, 3, 7, -37*2**32, -2*2**-537, -2*2**-538,
+                 2*2**-513),
+            (-7 * 2.0 ** -510, 5 * 2.0 ** -520, 17, -19.0, -6.25),
+            (11.25, -3.75, -0.625, 23.375, True, False, 7, Int(5)),
+        ]
+
+        for pool in pools:
+            for size in range(4):
+                for args1 in product(pool, repeat=size):
+                    for args2 in product(pool, repeat=size):
+                        args = (args1, args2)
+                        self.assertEqual(
+                            run(baseline_sumprod, *args),
+                            run(sumprod, *args),
+                            args,
+                        )
+
+    @requires_IEEE_754
+    @unittest.skipIf(HAVE_DOUBLE_ROUNDING,
+                         "sumprod() accuracy not guaranteed on machines with double rounding")
+    @support.cpython_only    # Other implementations may choose a different algorithm
+    @support.requires_resource('cpu')
+    def test_sumprod_extended_precision_accuracy(self):
+        import operator
+        from fractions import Fraction
+        from itertools import starmap
+        from collections import namedtuple
+        from math import log2, exp2, fabs
+        from random import choices, uniform, shuffle
+        from statistics import median
+
+        DotExample = namedtuple('DotExample', ('x', 'y', 'target_sumprod', 'condition'))
+
+        def DotExact(x, y):
+            vec1 = map(Fraction, x)
+            vec2 = map(Fraction, y)
+            return sum(starmap(operator.mul, zip(vec1, vec2, strict=True)))
+
+        def Condition(x, y):
+            return 2.0 * DotExact(map(abs, x), map(abs, y)) / abs(DotExact(x, y))
+
+        def linspace(lo, hi, n):
+            width = (hi - lo) / (n - 1)
+            return [lo + width * i for i in range(n)]
+
+        def GenDot(n, c):
+            """ Algorithm 6.1 (GenDot) works as follows. The condition number (5.7) of
+            the dot product xT y is proportional to the degree of cancellation. In
+            order to achieve a prescribed cancellation, we generate the first half of
+            the vectors x and y randomly within a large exponent range. This range is
+            chosen according to the anticipated condition number. The second half of x
+            and y is then constructed choosing xi randomly with decreasing exponent,
+            and calculating yi such that some cancellation occurs. Finally, we permute
+            the vectors x, y randomly and calculate the achieved condition number.
+            """
+
+            assert n >= 6
+            n2 = n // 2
+            x = [0.0] * n
+            y = [0.0] * n
+            b = log2(c)
+
+            # First half with exponents from 0 to |_b/2_| and random ints in between
+            e = choices(range(int(b/2)), k=n2)
+            e[0] = int(b / 2) + 1
+            e[-1] = 0.0
+
+            x[:n2] = [uniform(-1.0, 1.0) * exp2(p) for p in e]
+            y[:n2] = [uniform(-1.0, 1.0) * exp2(p) for p in e]
+
+            # Second half
+            e = list(map(round, linspace(b/2, 0.0 , n-n2)))
+            for i in range(n2, n):
+                x[i] = uniform(-1.0, 1.0) * exp2(e[i - n2])
+                y[i] = (uniform(-1.0, 1.0) * exp2(e[i - n2]) - DotExact(x, y)) / x[i]
+
+            # Shuffle
+            pairs = list(zip(x, y))
+            shuffle(pairs)
+            x, y = zip(*pairs)
+
+            return DotExample(x, y, DotExact(x, y), Condition(x, y))
+
+        def RelativeError(res, ex):
+            x, y, target_sumprod, condition = ex
+            n = DotExact(list(x) + [-res], list(y) + [1])
+            return fabs(n / target_sumprod)
+
+        def Trial(dotfunc, c, n):
+            ex = GenDot(10, c)
+            res = dotfunc(ex.x, ex.y)
+            return RelativeError(res, ex)
+
+        times = 1000          # Number of trials
+        n = 20                # Length of vectors
+        c = 1e30              # Target condition number
+
+        # If the following test fails, it means that the C math library
+        # implementation of fma() is not compliant with the C99 standard
+        # and is inaccurate.  To solve this problem, make a new build
+        # with the symbol UNRELIABLE_FMA defined.  That will enable a
+        # slower but accurate code path that avoids the fma() call.
+        relative_err = median(Trial(math.sumprod, c, n) for i in range(times))
+        self.assertLess(relative_err, 1e-16)
+
     def testModf(self):
         self.assertRaises(TypeError, math.modf)
 
@@ -1235,6 +1570,7 @@ def testPow(self):
         self.assertTrue(math.isnan(math.pow(2, NAN)))
         self.assertTrue(math.isnan(math.pow(0, NAN)))
         self.assertEqual(math.pow(1, NAN), 1)
+        self.assertRaises(OverflowError, math.pow, 1e+100, 1e+100)
 
         # pow(0., x)
         self.assertEqual(math.pow(0., INF), 0.)
@@ -1550,7 +1886,7 @@ def testTan(self):
         try:
             self.assertTrue(math.isnan(math.tan(INF)))
             self.assertTrue(math.isnan(math.tan(NINF)))
-        except:
+        except ValueError:
             self.assertRaises(ValueError, math.tan, INF)
             self.assertRaises(ValueError, math.tan, NINF)
         self.assertTrue(math.isnan(math.tan(NAN)))
@@ -1591,6 +1927,8 @@ def __trunc__(self):
                 return 23
         class TestNoTrunc:
             pass
+        class TestBadTrunc:
+            __trunc__ = BadDescr()
 
         self.assertEqual(math.trunc(TestTrunc()), 23)
         self.assertEqual(math.trunc(FloatTrunc()), 23)
@@ -1599,6 +1937,7 @@ class TestNoTrunc:
         self.assertRaises(TypeError, math.trunc, 1, 2)
         self.assertRaises(TypeError, math.trunc, FloatLike(23.5))
         self.assertRaises(TypeError, math.trunc, TestNoTrunc())
+        self.assertRaises(ValueError, math.trunc, TestBadTrunc())
 
     def testIsfinite(self):
         self.assertTrue(math.isfinite(0.0))
@@ -1626,11 +1965,11 @@ def testIsinf(self):
         self.assertFalse(math.isinf(0.))
         self.assertFalse(math.isinf(1.))
 
-    @requires_IEEE_754
     def test_nan_constant(self):
+        # `math.nan` must be a quiet NaN with positive sign bit
         self.assertTrue(math.isnan(math.nan))
+        self.assertEqual(math.copysign(1., math.nan), 1.)
 
-    @requires_IEEE_754
     def test_inf_constant(self):
         self.assertTrue(math.isinf(math.inf))
         self.assertGreater(math.inf, 0.0)
@@ -1719,6 +2058,13 @@ def test_testfile(self):
             except OverflowError:
                 result = 'OverflowError'
 
+            # C99+ says for math.h's sqrt: If the argument is +∞ or ±0, it is
+            # returned, unmodified.  On another hand, for csqrt: If z is ±0+0i,
+            # the result is +0+0i.  Lets correct zero sign of er to follow
+            # first convention.
+            if id in ['sqrt0002', 'sqrt0003', 'sqrt1001', 'sqrt1023']:
+                er = math.copysign(er, ar)
+
             # Default tolerances
             ulp_tol, abs_tol = 5, 0.0
 
@@ -1802,6 +2148,8 @@ def test_mtestfile(self):
                       '\n  '.join(failures))
 
     def test_prod(self):
+        from fractions import Fraction as F
+
         prod = math.prod
         self.assertEqual(prod([]), 1)
         self.assertEqual(prod([], start=5), 5)
@@ -1813,6 +2161,14 @@ def test_prod(self):
         self.assertEqual(prod([1.0, 2.0, 3.0, 4.0, 5.0]), 120.0)
         self.assertEqual(prod([1, 2, 3, 4.0, 5.0]), 120.0)
         self.assertEqual(prod([1.0, 2.0, 3.0, 4, 5]), 120.0)
+        self.assertEqual(prod([1., F(3, 2)]), 1.5)
+
+        # Error in multiplication
+        class BadMultiply:
+            def __rmul__(self, other):
+                raise RuntimeError
+        with self.assertRaises(RuntimeError):
+            prod([10., BadMultiply()])
 
         # Test overflow in fast-path for integers
         self.assertEqual(prod([1, 1, 2**32, 1, 1]), 2**32)
@@ -2044,11 +2400,20 @@ def test_nextafter(self):
                          float.fromhex('0x1.fffffffffffffp-1'))
         self.assertEqual(math.nextafter(1.0, INF),
                          float.fromhex('0x1.0000000000001p+0'))
+        self.assertEqual(math.nextafter(1.0, -INF, steps=1),
+                         float.fromhex('0x1.fffffffffffffp-1'))
+        self.assertEqual(math.nextafter(1.0, INF, steps=1),
+                         float.fromhex('0x1.0000000000001p+0'))
+        self.assertEqual(math.nextafter(1.0, -INF, steps=3),
+                         float.fromhex('0x1.ffffffffffffdp-1'))
+        self.assertEqual(math.nextafter(1.0, INF, steps=3),
+                         float.fromhex('0x1.0000000000003p+0'))
 
         # x == y: y is returned
-        self.assertEqual(math.nextafter(2.0, 2.0), 2.0)
-        self.assertEqualSign(math.nextafter(-0.0, +0.0), +0.0)
-        self.assertEqualSign(math.nextafter(+0.0, -0.0), -0.0)
+        for steps in range(1, 5):
+            self.assertEqual(math.nextafter(2.0, 2.0, steps=steps), 2.0)
+            self.assertEqualSign(math.nextafter(-0.0, +0.0, steps=steps), +0.0)
+            self.assertEqualSign(math.nextafter(+0.0, -0.0, steps=steps), -0.0)
 
         # around 0.0
         smallest_subnormal = sys.float_info.min * sys.float_info.epsilon
@@ -2073,6 +2438,11 @@ def test_nextafter(self):
         self.assertIsNaN(math.nextafter(1.0, NAN))
         self.assertIsNaN(math.nextafter(NAN, NAN))
 
+        self.assertEqual(1.0, math.nextafter(1.0, INF, steps=0))
+        with self.assertRaises(ValueError):
+            math.nextafter(1.0, INF, steps=-1)
+
+
     @requires_IEEE_754
     def test_ulp(self):
         self.assertEqual(math.ulp(1.0), sys.float_info.epsilon)
@@ -2112,6 +2482,14 @@ def __float__(self):
             # argument to a float.
             self.assertFalse(getattr(y, "converted", False))
 
+    def test_input_exceptions(self):
+        self.assertRaises(TypeError, math.exp, "spam")
+        self.assertRaises(TypeError, math.erf, "spam")
+        self.assertRaises(TypeError, math.atan2, "spam", 1.0)
+        self.assertRaises(TypeError, math.atan2, 1.0, "spam")
+        self.assertRaises(TypeError, math.atan2, 1.0)
+        self.assertRaises(TypeError, math.atan2, 1.0, 2.0, 3.0)
+
     # Custom assertions.
 
     def assertIsNaN(self, value):
@@ -2252,7 +2630,7 @@ def test_fractions(self):
 
 def load_tests(loader, tests, pattern):
     from doctest import DocFileSuite
-    # tests.addTest(DocFileSuite("ieee754.txt"))
+    tests.addTest(DocFileSuite("ieee754.txt"))
     return tests
 
 if __name__ == '__main__':
diff --git a/Lib/test/test_random.py b/Lib/test/test_random.py
index 70bfbf09b5..2cceaea244 100644
--- a/Lib/test/test_random.py
+++ b/Lib/test/test_random.py
@@ -22,8 +22,6 @@ def randomlist(self, n):
         """Helper function to make a list of random numbers"""
         return [self.gen.random() for i in range(n)]
 
-    # TODO: RUSTPYTHON AttributeError: 'super' object has no attribute 'getstate'
-    @unittest.expectedFailure
     def test_autoseed(self):
         self.gen.seed()
         state1 = self.gen.getstate()
@@ -32,8 +30,6 @@ def test_autoseed(self):
         state2 = self.gen.getstate()
         self.assertNotEqual(state1, state2)
 
-    # TODO: RUSTPYTHON AttributeError: 'super' object has no attribute 'getstate'
-    @unittest.expectedFailure
     def test_saverestore(self):
         N = 1000
         self.gen.seed()
@@ -60,7 +56,6 @@ def __hash__(self):
         self.assertRaises(TypeError, self.gen.seed, 1, 2, 3, 4)
         self.assertRaises(TypeError, type(self.gen), [])
 
-    @unittest.skip("TODO: RUSTPYTHON, TypeError: Expected type 'bytes', not 'bytearray'")
     def test_seed_no_mutate_bug_44018(self):
         a = bytearray(b'1234')
         self.gen.seed(a)
@@ -386,8 +381,6 @@ def test_getrandbits(self):
         self.assertRaises(ValueError, self.gen.getrandbits, -1)
         self.assertRaises(TypeError, self.gen.getrandbits, 10.1)
 
-    # TODO: RUSTPYTHON AttributeError: 'super' object has no attribute 'getstate'
-    @unittest.expectedFailure
     def test_pickling(self):
         for proto in range(pickle.HIGHEST_PROTOCOL + 1):
             state = pickle.dumps(self.gen, proto)
@@ -396,8 +389,6 @@ def test_pickling(self):
             restoredseq = [newgen.random() for i in range(10)]
             self.assertEqual(origseq, restoredseq)
 
-    # TODO: RUSTPYTHON AttributeError: 'super' object has no attribute 'getstate'
-    @unittest.expectedFailure
     def test_bug_1727780(self):
         # verify that version-2-pickles can be loaded
         # fine, whether they are created on 32-bit or 64-bit
@@ -600,11 +591,6 @@ def test_bug_42008(self):
 class MersenneTwister_TestBasicOps(TestBasicOps, unittest.TestCase):
     gen = random.Random()
 
-    # TODO: RUSTPYTHON, TypeError: Expected type 'bytes', not 'bytearray'
-    @unittest.expectedFailure
-    def test_seed_no_mutate_bug_44018(self):  # TODO: RUSTPYTHON, remove when this passes
-        super().test_seed_no_mutate_bug_44018()  # TODO: RUSTPYTHON, remove when this passes
-
     def test_guaranteed_stable(self):
         # These sequences are guaranteed to stay the same across versions of python
         self.gen.seed(3456147, version=1)
@@ -675,8 +661,6 @@ def test_bug_31482(self):
     def test_setstate_first_arg(self):
         self.assertRaises(ValueError, self.gen.setstate, (1, None, None))
 
-    # TODO: RUSTPYTHON AttributeError: 'super' object has no attribute 'getstate'
-    @unittest.expectedFailure
     def test_setstate_middle_arg(self):
         start_state = self.gen.getstate()
         # Wrong type, s/b tuple
@@ -1012,8 +996,6 @@ def gamma(z, sqrt2pi=(2.0*pi)**0.5):
     ])
 
 class TestDistributions(unittest.TestCase):
-    # TODO: RUSTPYTHON ValueError: math domain error
-    @unittest.expectedFailure
     def test_zeroinputs(self):
         # Verify that distributions can handle a series of zero inputs'
         g = random.Random()
@@ -1284,15 +1266,6 @@ def test_betavariate_return_zero(self, gammavariate_mock):
 
 
 class TestRandomSubclassing(unittest.TestCase):
-    # TODO: RUSTPYTHON Unexpected keyword argument newarg
-    @unittest.expectedFailure
-    def test_random_subclass_with_kwargs(self):
-        # SF bug #1486663 -- this used to erroneously raise a TypeError
-        class Subclass(random.Random):
-            def __init__(self, newarg=None):
-                random.Random.__init__(self)
-        Subclass(newarg=1)
-
     def test_subclasses_overriding_methods(self):
         # Subclasses with an overridden random, but only the original
         # getrandbits method should not rely on getrandbits in for randrange,
diff --git a/Lib/test/test_smtplib.py b/Lib/test/test_smtplib.py
new file mode 100644
index 0000000000..a36d7bbe2a
--- /dev/null
+++ b/Lib/test/test_smtplib.py
@@ -0,0 +1,1568 @@
+import base64
+import email.mime.text
+from email.message import EmailMessage
+from email.base64mime import body_encode as encode_base64
+import email.utils
+import hashlib
+import hmac
+import socket
+import smtplib
+import io
+import re
+import sys
+import time
+import select
+import errno
+import textwrap
+import threading
+
+import unittest
+from test import support, mock_socket
+from test.support import hashlib_helper
+from test.support import socket_helper
+from test.support import threading_helper
+from test.support import asyncore
+from test.support import smtpd
+from unittest.mock import Mock
+
+
+support.requires_working_socket(module=True)
+
+HOST = socket_helper.HOST
+
+if sys.platform == 'darwin':
+    # select.poll returns a select.POLLHUP at the end of the tests
+    # on darwin, so just ignore it
+    def handle_expt(self):
+        pass
+    smtpd.SMTPChannel.handle_expt = handle_expt
+
+
+def server(evt, buf, serv):
+    serv.listen()
+    evt.set()
+    try:
+        conn, addr = serv.accept()
+    except TimeoutError:
+        pass
+    else:
+        n = 500
+        while buf and n > 0:
+            r, w, e = select.select([], [conn], [])
+            if w:
+                sent = conn.send(buf)
+                buf = buf[sent:]
+
+            n -= 1
+
+        conn.close()
+    finally:
+        serv.close()
+        evt.set()
+
+class GeneralTests:
+
+    def setUp(self):
+        smtplib.socket = mock_socket
+        self.port = 25
+
+    def tearDown(self):
+        smtplib.socket = socket
+
+    # This method is no longer used but is retained for backward compatibility,
+    # so test to make sure it still works.
+    def testQuoteData(self):
+        teststr  = "abc\n.jkl\rfoo\r\n..blue"
+        expected = "abc\r\n..jkl\r\nfoo\r\n...blue"
+        self.assertEqual(expected, smtplib.quotedata(teststr))
+
+    def testBasic1(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        # connects
+        client = self.client(HOST, self.port)
+        client.close()
+
+    def testSourceAddress(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        # connects
+        client = self.client(HOST, self.port,
+                             source_address=('127.0.0.1',19876))
+        self.assertEqual(client.source_address, ('127.0.0.1', 19876))
+        client.close()
+
+    def testBasic2(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        # connects, include port in host name
+        client = self.client("%s:%s" % (HOST, self.port))
+        client.close()
+
+    def testLocalHostName(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        # check that supplied local_hostname is used
+        client = self.client(HOST, self.port, local_hostname="testhost")
+        self.assertEqual(client.local_hostname, "testhost")
+        client.close()
+
+    def testTimeoutDefault(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        self.assertIsNone(mock_socket.getdefaulttimeout())
+        mock_socket.setdefaulttimeout(30)
+        self.assertEqual(mock_socket.getdefaulttimeout(), 30)
+        try:
+            client = self.client(HOST, self.port)
+        finally:
+            mock_socket.setdefaulttimeout(None)
+        self.assertEqual(client.sock.gettimeout(), 30)
+        client.close()
+
+    def testTimeoutNone(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        self.assertIsNone(socket.getdefaulttimeout())
+        socket.setdefaulttimeout(30)
+        try:
+            client = self.client(HOST, self.port, timeout=None)
+        finally:
+            socket.setdefaulttimeout(None)
+        self.assertIsNone(client.sock.gettimeout())
+        client.close()
+
+    def testTimeoutZero(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        with self.assertRaises(ValueError):
+            self.client(HOST, self.port, timeout=0)
+
+    def testTimeoutValue(self):
+        mock_socket.reply_with(b"220 Hola mundo")
+        client = self.client(HOST, self.port, timeout=30)
+        self.assertEqual(client.sock.gettimeout(), 30)
+        client.close()
+
+    def test_debuglevel(self):
+        mock_socket.reply_with(b"220 Hello world")
+        client = self.client()
+        client.set_debuglevel(1)
+        with support.captured_stderr() as stderr:
+            client.connect(HOST, self.port)
+        client.close()
+        expected = re.compile(r"^connect:", re.MULTILINE)
+        self.assertRegex(stderr.getvalue(), expected)
+
+    def test_debuglevel_2(self):
+        mock_socket.reply_with(b"220 Hello world")
+        client = self.client()
+        client.set_debuglevel(2)
+        with support.captured_stderr() as stderr:
+            client.connect(HOST, self.port)
+        client.close()
+        expected = re.compile(r"^\d{2}:\d{2}:\d{2}\.\d{6} connect: ",
+                              re.MULTILINE)
+        self.assertRegex(stderr.getvalue(), expected)
+
+
+class SMTPGeneralTests(GeneralTests, unittest.TestCase):
+
+    client = smtplib.SMTP
+
+
+class LMTPGeneralTests(GeneralTests, unittest.TestCase):
+
+    client = smtplib.LMTP
+
+    @unittest.skipUnless(hasattr(socket, 'AF_UNIX'), "test requires Unix domain socket")
+    def testUnixDomainSocketTimeoutDefault(self):
+        local_host = '/some/local/lmtp/delivery/program'
+        mock_socket.reply_with(b"220 Hello world")
+        try:
+            client = self.client(local_host, self.port)
+        finally:
+            mock_socket.setdefaulttimeout(None)
+        self.assertIsNone(client.sock.gettimeout())
+        client.close()
+
+    def testTimeoutZero(self):
+        super().testTimeoutZero()
+        local_host = '/some/local/lmtp/delivery/program'
+        with self.assertRaises(ValueError):
+            self.client(local_host, timeout=0)
+
+# Test server thread using the specified SMTP server class
+def debugging_server(serv, serv_evt, client_evt):
+    serv_evt.set()
+
+    try:
+        if hasattr(select, 'poll'):
+            poll_fun = asyncore.poll2
+        else:
+            poll_fun = asyncore.poll
+
+        n = 1000
+        while asyncore.socket_map and n > 0:
+            poll_fun(0.01, asyncore.socket_map)
+
+            # when the client conversation is finished, it will
+            # set client_evt, and it's then ok to kill the server
+            if client_evt.is_set():
+                serv.close()
+                break
+
+            n -= 1
+
+    except TimeoutError:
+        pass
+    finally:
+        if not client_evt.is_set():
+            # allow some time for the client to read the result
+            time.sleep(0.5)
+            serv.close()
+        asyncore.close_all()
+        serv_evt.set()
+
+MSG_BEGIN = '---------- MESSAGE FOLLOWS ----------\n'
+MSG_END = '------------ END MESSAGE ------------\n'
+
+# NOTE: Some SMTP objects in the tests below are created with a non-default
+# local_hostname argument to the constructor, since (on some systems) the FQDN
+# lookup caused by the default local_hostname sometimes takes so long that the
+# test server times out, causing the test to fail.
+
+# Test behavior of smtpd.DebuggingServer
+class DebuggingServerTests(unittest.TestCase):
+
+    maxDiff = None
+
+    def setUp(self):
+        self.thread_key = threading_helper.threading_setup()
+        self.real_getfqdn = socket.getfqdn
+        socket.getfqdn = mock_socket.getfqdn
+        # temporarily replace sys.stdout to capture DebuggingServer output
+        self.old_stdout = sys.stdout
+        self.output = io.StringIO()
+        sys.stdout = self.output
+
+        self.serv_evt = threading.Event()
+        self.client_evt = threading.Event()
+        # Capture SMTPChannel debug output
+        self.old_DEBUGSTREAM = smtpd.DEBUGSTREAM
+        smtpd.DEBUGSTREAM = io.StringIO()
+        # Pick a random unused port by passing 0 for the port number
+        self.serv = smtpd.DebuggingServer((HOST, 0), ('nowhere', -1),
+                                          decode_data=True)
+        # Keep a note of what server host and port were assigned
+        self.host, self.port = self.serv.socket.getsockname()[:2]
+        serv_args = (self.serv, self.serv_evt, self.client_evt)
+        self.thread = threading.Thread(target=debugging_server, args=serv_args)
+        self.thread.start()
+
+        # wait until server thread has assigned a port number
+        self.serv_evt.wait()
+        self.serv_evt.clear()
+
+    def tearDown(self):
+        socket.getfqdn = self.real_getfqdn
+        # indicate that the client is finished
+        self.client_evt.set()
+        # wait for the server thread to terminate
+        self.serv_evt.wait()
+        threading_helper.join_thread(self.thread)
+        # restore sys.stdout
+        sys.stdout = self.old_stdout
+        # restore DEBUGSTREAM
+        smtpd.DEBUGSTREAM.close()
+        smtpd.DEBUGSTREAM = self.old_DEBUGSTREAM
+        del self.thread
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self.thread_key)
+
+    def get_output_without_xpeer(self):
+        test_output = self.output.getvalue()
+        return re.sub(r'(.*?)^X-Peer:\s*\S+\n(.*)', r'\1\2',
+                      test_output, flags=re.MULTILINE|re.DOTALL)
+
+    def testBasic(self):
+        # connect
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.quit()
+
+    def testSourceAddress(self):
+        # connect
+        src_port = socket_helper.find_unused_port()
+        try:
+            smtp = smtplib.SMTP(self.host, self.port, local_hostname='localhost',
+                                timeout=support.LOOPBACK_TIMEOUT,
+                                source_address=(self.host, src_port))
+            self.addCleanup(smtp.close)
+            self.assertEqual(smtp.source_address, (self.host, src_port))
+            self.assertEqual(smtp.local_hostname, 'localhost')
+            smtp.quit()
+        except OSError as e:
+            if e.errno == errno.EADDRINUSE:
+                self.skipTest("couldn't bind to source port %d" % src_port)
+            raise
+
+    def testNOOP(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        expected = (250, b'OK')
+        self.assertEqual(smtp.noop(), expected)
+        smtp.quit()
+
+    def testRSET(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        expected = (250, b'OK')
+        self.assertEqual(smtp.rset(), expected)
+        smtp.quit()
+
+    def testELHO(self):
+        # EHLO isn't implemented in DebuggingServer
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        expected = (250, b'\nSIZE 33554432\nHELP')
+        self.assertEqual(smtp.ehlo(), expected)
+        smtp.quit()
+
+    def testEXPNNotImplemented(self):
+        # EXPN isn't implemented in DebuggingServer
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        expected = (502, b'EXPN not implemented')
+        smtp.putcmd('EXPN')
+        self.assertEqual(smtp.getreply(), expected)
+        smtp.quit()
+
+    def test_issue43124_putcmd_escapes_newline(self):
+        # see: https://bugs.python.org/issue43124
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        with self.assertRaises(ValueError) as exc:
+            smtp.putcmd('helo\nX-INJECTED')
+        self.assertIn("prohibited newline characters", str(exc.exception))
+        smtp.quit()
+
+    def testVRFY(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        expected = (252, b'Cannot VRFY user, but will accept message ' + \
+                    b'and attempt delivery')
+        self.assertEqual(smtp.vrfy('nobody@nowhere.com'), expected)
+        self.assertEqual(smtp.verify('nobody@nowhere.com'), expected)
+        smtp.quit()
+
+    def testSecondHELO(self):
+        # check that a second HELO returns a message that it's a duplicate
+        # (this behavior is specific to smtpd.SMTPChannel)
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.helo()
+        expected = (503, b'Duplicate HELO/EHLO')
+        self.assertEqual(smtp.helo(), expected)
+        smtp.quit()
+
+    def testHELP(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        self.assertEqual(smtp.help(), b'Supported commands: EHLO HELO MAIL ' + \
+                         b'RCPT DATA RSET NOOP QUIT VRFY')
+        smtp.quit()
+
+    def testSend(self):
+        # connect and send mail
+        m = 'A test message'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.sendmail('John', 'Sally', m)
+        # XXX(nnorwitz): this test is flaky and dies with a bad file descriptor
+        # in asyncore.  This sleep might help, but should really be fixed
+        # properly by using an Event variable.
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m, MSG_END)
+        self.assertEqual(self.output.getvalue(), mexpect)
+
+    def testSendBinary(self):
+        m = b'A test message'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.sendmail('John', 'Sally', m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.decode('ascii'), MSG_END)
+        self.assertEqual(self.output.getvalue(), mexpect)
+
+    def testSendNeedingDotQuote(self):
+        # Issue 12283
+        m = '.A test\n.mes.sage.'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.sendmail('John', 'Sally', m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m, MSG_END)
+        self.assertEqual(self.output.getvalue(), mexpect)
+
+    def test_issue43124_escape_localhostname(self):
+        # see: https://bugs.python.org/issue43124
+        # connect and send mail
+        m = 'wazzuuup\nlinetwo'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='hi\nX-INJECTED',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        with self.assertRaises(ValueError) as exc:
+            smtp.sendmail("hi@me.com", "you@me.com", m)
+        self.assertIn(
+            "prohibited newline characters: ehlo hi\\nX-INJECTED",
+            str(exc.exception),
+        )
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        self.assertNotIn("X-INJECTED", debugout)
+
+    def test_issue43124_escape_options(self):
+        # see: https://bugs.python.org/issue43124
+        # connect and send mail
+        m = 'wazzuuup\nlinetwo'
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+
+        self.addCleanup(smtp.close)
+        smtp.sendmail("hi@me.com", "you@me.com", m)
+        with self.assertRaises(ValueError) as exc:
+            smtp.mail("hi@me.com", ["X-OPTION\nX-INJECTED-1", "X-OPTION2\nX-INJECTED-2"])
+        msg = str(exc.exception)
+        self.assertIn("prohibited newline characters", msg)
+        self.assertIn("X-OPTION\\nX-INJECTED-1 X-OPTION2\\nX-INJECTED-2", msg)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        self.assertNotIn("X-OPTION", debugout)
+        self.assertNotIn("X-OPTION2", debugout)
+        self.assertNotIn("X-INJECTED-1", debugout)
+        self.assertNotIn("X-INJECTED-2", debugout)
+
+    def testSendNullSender(self):
+        m = 'A test message'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.sendmail('<>', 'Sally', m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m, MSG_END)
+        self.assertEqual(self.output.getvalue(), mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: <>$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+
+    def testSendMessage(self):
+        m = email.mime.text.MIMEText('A test message')
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m, from_addr='John', to_addrs='Sally')
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # Remove the X-Peer header that DebuggingServer adds as figuring out
+        # exactly what IP address format is put there is not easy (and
+        # irrelevant to our test).  Typically 127.0.0.1 or ::1, but it is
+        # not always the same as socket.gethostbyname(HOST). :(
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+
+    def testSendMessageWithAddresses(self):
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'foo@bar.com'
+        m['To'] = 'John'
+        m['CC'] = 'Sally, Fred'
+        m['Bcc'] = 'John Root <root@localhost>, "Dinsdale" <warped@silly.walks.com>'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+        # make sure the Bcc header is still in the message.
+        self.assertEqual(m['Bcc'], 'John Root <root@localhost>, "Dinsdale" '
+                                   '<warped@silly.walks.com>')
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # Remove the X-Peer header that DebuggingServer adds.
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        # The Bcc header should not be transmitted.
+        del m['Bcc']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: foo@bar.com$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+        for addr in ('John', 'Sally', 'Fred', 'root@localhost',
+                     'warped@silly.walks.com'):
+            to_addr = re.compile(r"^recips: .*'{}'.*$".format(addr),
+                                 re.MULTILINE)
+            self.assertRegex(debugout, to_addr)
+
+    def testSendMessageWithSomeAddresses(self):
+        # Make sure nothing breaks if not all of the three 'to' headers exist
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'foo@bar.com'
+        m['To'] = 'John, Dinsdale'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # Remove the X-Peer header that DebuggingServer adds.
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: foo@bar.com$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+        for addr in ('John', 'Dinsdale'):
+            to_addr = re.compile(r"^recips: .*'{}'.*$".format(addr),
+                                 re.MULTILINE)
+            self.assertRegex(debugout, to_addr)
+
+    def testSendMessageWithSpecifiedAddresses(self):
+        # Make sure addresses specified in call override those in message.
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'foo@bar.com'
+        m['To'] = 'John, Dinsdale'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m, from_addr='joe@example.com', to_addrs='foo@example.net')
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # Remove the X-Peer header that DebuggingServer adds.
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: joe@example.com$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+        for addr in ('John', 'Dinsdale'):
+            to_addr = re.compile(r"^recips: .*'{}'.*$".format(addr),
+                                 re.MULTILINE)
+            self.assertNotRegex(debugout, to_addr)
+        recip = re.compile(r"^recips: .*'foo@example.net'.*$", re.MULTILINE)
+        self.assertRegex(debugout, recip)
+
+    def testSendMessageWithMultipleFrom(self):
+        # Sender overrides To
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'Bernard, Bianca'
+        m['Sender'] = 'the_rescuers@Rescue-Aid-Society.com'
+        m['To'] = 'John, Dinsdale'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # Remove the X-Peer header that DebuggingServer adds.
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: the_rescuers@Rescue-Aid-Society.com$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+        for addr in ('John', 'Dinsdale'):
+            to_addr = re.compile(r"^recips: .*'{}'.*$".format(addr),
+                                 re.MULTILINE)
+            self.assertRegex(debugout, to_addr)
+
+    def testSendMessageResent(self):
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'foo@bar.com'
+        m['To'] = 'John'
+        m['CC'] = 'Sally, Fred'
+        m['Bcc'] = 'John Root <root@localhost>, "Dinsdale" <warped@silly.walks.com>'
+        m['Resent-Date'] = 'Thu, 1 Jan 1970 17:42:00 +0000'
+        m['Resent-From'] = 'holy@grail.net'
+        m['Resent-To'] = 'Martha <my_mom@great.cooker.com>, Jeff'
+        m['Resent-Bcc'] = 'doe@losthope.net'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.send_message(m)
+        # XXX (see comment in testSend)
+        time.sleep(0.01)
+        smtp.quit()
+
+        self.client_evt.set()
+        self.serv_evt.wait()
+        self.output.flush()
+        # The Resent-Bcc headers are deleted before serialization.
+        del m['Bcc']
+        del m['Resent-Bcc']
+        # Remove the X-Peer header that DebuggingServer adds.
+        test_output = self.get_output_without_xpeer()
+        del m['X-Peer']
+        mexpect = '%s%s\n%s' % (MSG_BEGIN, m.as_string(), MSG_END)
+        self.assertEqual(test_output, mexpect)
+        debugout = smtpd.DEBUGSTREAM.getvalue()
+        sender = re.compile("^sender: holy@grail.net$", re.MULTILINE)
+        self.assertRegex(debugout, sender)
+        for addr in ('my_mom@great.cooker.com', 'Jeff', 'doe@losthope.net'):
+            to_addr = re.compile(r"^recips: .*'{}'.*$".format(addr),
+                                 re.MULTILINE)
+            self.assertRegex(debugout, to_addr)
+
+    def testSendMessageMultipleResentRaises(self):
+        m = email.mime.text.MIMEText('A test message')
+        m['From'] = 'foo@bar.com'
+        m['To'] = 'John'
+        m['CC'] = 'Sally, Fred'
+        m['Bcc'] = 'John Root <root@localhost>, "Dinsdale" <warped@silly.walks.com>'
+        m['Resent-Date'] = 'Thu, 1 Jan 1970 17:42:00 +0000'
+        m['Resent-From'] = 'holy@grail.net'
+        m['Resent-To'] = 'Martha <my_mom@great.cooker.com>, Jeff'
+        m['Resent-Bcc'] = 'doe@losthope.net'
+        m['Resent-Date'] = 'Thu, 2 Jan 1970 17:42:00 +0000'
+        m['Resent-To'] = 'holy@grail.net'
+        m['Resent-From'] = 'Martha <my_mom@great.cooker.com>, Jeff'
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        with self.assertRaises(ValueError):
+            smtp.send_message(m)
+        smtp.close()
+
+class NonConnectingTests(unittest.TestCase):
+
+    def testNotConnected(self):
+        # Test various operations on an unconnected SMTP object that
+        # should raise exceptions (at present the attempt in SMTP.send
+        # to reference the nonexistent 'sock' attribute of the SMTP object
+        # causes an AttributeError)
+        smtp = smtplib.SMTP()
+        self.assertRaises(smtplib.SMTPServerDisconnected, smtp.ehlo)
+        self.assertRaises(smtplib.SMTPServerDisconnected,
+                          smtp.send, 'test msg')
+
+    def testNonnumericPort(self):
+        # check that non-numeric port raises OSError
+        self.assertRaises(OSError, smtplib.SMTP,
+                          "localhost", "bogus")
+        self.assertRaises(OSError, smtplib.SMTP,
+                          "localhost:bogus")
+
+    def testSockAttributeExists(self):
+        # check that sock attribute is present outside of a connect() call
+        # (regression test, the previous behavior raised an
+        #  AttributeError: 'SMTP' object has no attribute 'sock')
+        with smtplib.SMTP() as smtp:
+            self.assertIsNone(smtp.sock)
+
+
+class DefaultArgumentsTests(unittest.TestCase):
+
+    def setUp(self):
+        self.msg = EmailMessage()
+        self.msg['From'] = 'Páolo <főo@bar.com>'
+        self.smtp = smtplib.SMTP()
+        self.smtp.ehlo = Mock(return_value=(200, 'OK'))
+        self.smtp.has_extn, self.smtp.sendmail = Mock(), Mock()
+
+    def testSendMessage(self):
+        expected_mail_options = ('SMTPUTF8', 'BODY=8BITMIME')
+        self.smtp.send_message(self.msg)
+        self.smtp.send_message(self.msg)
+        self.assertEqual(self.smtp.sendmail.call_args_list[0][0][3],
+                         expected_mail_options)
+        self.assertEqual(self.smtp.sendmail.call_args_list[1][0][3],
+                         expected_mail_options)
+
+    def testSendMessageWithMailOptions(self):
+        mail_options = ['STARTTLS']
+        expected_mail_options = ('STARTTLS', 'SMTPUTF8', 'BODY=8BITMIME')
+        self.smtp.send_message(self.msg, None, None, mail_options)
+        self.assertEqual(mail_options, ['STARTTLS'])
+        self.assertEqual(self.smtp.sendmail.call_args_list[0][0][3],
+                         expected_mail_options)
+
+
+# test response of client to a non-successful HELO message
+class BadHELOServerTests(unittest.TestCase):
+
+    def setUp(self):
+        smtplib.socket = mock_socket
+        mock_socket.reply_with(b"199 no hello for you!")
+        self.old_stdout = sys.stdout
+        self.output = io.StringIO()
+        sys.stdout = self.output
+        self.port = 25
+
+    def tearDown(self):
+        smtplib.socket = socket
+        sys.stdout = self.old_stdout
+
+    def testFailingHELO(self):
+        self.assertRaises(smtplib.SMTPConnectError, smtplib.SMTP,
+                          HOST, self.port, 'localhost', 3)
+
+
+class TooLongLineTests(unittest.TestCase):
+    respdata = b'250 OK' + (b'.' * smtplib._MAXLINE * 2) + b'\n'
+
+    def setUp(self):
+        self.thread_key = threading_helper.threading_setup()
+        self.old_stdout = sys.stdout
+        self.output = io.StringIO()
+        sys.stdout = self.output
+
+        self.evt = threading.Event()
+        self.sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        self.sock.settimeout(15)
+        self.port = socket_helper.bind_port(self.sock)
+        servargs = (self.evt, self.respdata, self.sock)
+        self.thread = threading.Thread(target=server, args=servargs)
+        self.thread.start()
+        self.evt.wait()
+        self.evt.clear()
+
+    def tearDown(self):
+        self.evt.wait()
+        sys.stdout = self.old_stdout
+        threading_helper.join_thread(self.thread)
+        del self.thread
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self.thread_key)
+
+    def testLineTooLong(self):
+        self.assertRaises(smtplib.SMTPResponseException, smtplib.SMTP,
+                          HOST, self.port, 'localhost', 3)
+
+
+sim_users = {'Mr.A@somewhere.com':'John A',
+             'Ms.B@xn--fo-fka.com':'Sally B',
+             'Mrs.C@somewhereesle.com':'Ruth C',
+             }
+
+sim_auth = ('Mr.A@somewhere.com', 'somepassword')
+sim_cram_md5_challenge = ('PENCeUxFREJoU0NnbmhNWitOMjNGNn'
+                          'dAZWx3b29kLmlubm9zb2Z0LmNvbT4=')
+sim_lists = {'list-1':['Mr.A@somewhere.com','Mrs.C@somewhereesle.com'],
+             'list-2':['Ms.B@xn--fo-fka.com',],
+             }
+
+# Simulated SMTP channel & server
+class ResponseException(Exception): pass
+class SimSMTPChannel(smtpd.SMTPChannel):
+
+    quit_response = None
+    mail_response = None
+    rcpt_response = None
+    data_response = None
+    rcpt_count = 0
+    rset_count = 0
+    disconnect = 0
+    AUTH = 99    # Add protocol state to enable auth testing.
+    authenticated_user = None
+
+    def __init__(self, extra_features, *args, **kw):
+        self._extrafeatures = ''.join(
+            [ "250-{0}\r\n".format(x) for x in extra_features ])
+        super(SimSMTPChannel, self).__init__(*args, **kw)
+
+    # AUTH related stuff.  It would be nice if support for this were in smtpd.
+    def found_terminator(self):
+        if self.smtp_state == self.AUTH:
+            line = self._emptystring.join(self.received_lines)
+            print('Data:', repr(line), file=smtpd.DEBUGSTREAM)
+            self.received_lines = []
+            try:
+                self.auth_object(line)
+            except ResponseException as e:
+                self.smtp_state = self.COMMAND
+                self.push('%s %s' % (e.smtp_code, e.smtp_error))
+            return
+        super().found_terminator()
+
+
+    def smtp_AUTH(self, arg):
+        if not self.seen_greeting:
+            self.push('503 Error: send EHLO first')
+            return
+        if not self.extended_smtp or 'AUTH' not in self._extrafeatures:
+            self.push('500 Error: command "AUTH" not recognized')
+            return
+        if self.authenticated_user is not None:
+            self.push(
+                '503 Bad sequence of commands: already authenticated')
+            return
+        args = arg.split()
+        if len(args) not in [1, 2]:
+            self.push('501 Syntax: AUTH <mechanism> [initial-response]')
+            return
+        auth_object_name = '_auth_%s' % args[0].lower().replace('-', '_')
+        try:
+            self.auth_object = getattr(self, auth_object_name)
+        except AttributeError:
+            self.push('504 Command parameter not implemented: unsupported '
+                      ' authentication mechanism {!r}'.format(auth_object_name))
+            return
+        self.smtp_state = self.AUTH
+        self.auth_object(args[1] if len(args) == 2 else None)
+
+    def _authenticated(self, user, valid):
+        if valid:
+            self.authenticated_user = user
+            self.push('235 Authentication Succeeded')
+        else:
+            self.push('535 Authentication credentials invalid')
+        self.smtp_state = self.COMMAND
+
+    def _decode_base64(self, string):
+        return base64.decodebytes(string.encode('ascii')).decode('utf-8')
+
+    def _auth_plain(self, arg=None):
+        if arg is None:
+            self.push('334 ')
+        else:
+            logpass = self._decode_base64(arg)
+            try:
+                *_, user, password = logpass.split('\0')
+            except ValueError as e:
+                self.push('535 Splitting response {!r} into user and password'
+                          ' failed: {}'.format(logpass, e))
+                return
+            self._authenticated(user, password == sim_auth[1])
+
+    def _auth_login(self, arg=None):
+        if arg is None:
+            # base64 encoded 'Username:'
+            self.push('334 VXNlcm5hbWU6')
+        elif not hasattr(self, '_auth_login_user'):
+            self._auth_login_user = self._decode_base64(arg)
+            # base64 encoded 'Password:'
+            self.push('334 UGFzc3dvcmQ6')
+        else:
+            password = self._decode_base64(arg)
+            self._authenticated(self._auth_login_user, password == sim_auth[1])
+            del self._auth_login_user
+
+    def _auth_buggy(self, arg=None):
+        # This AUTH mechanism will 'trap' client in a neverending 334
+        # base64 encoded 'BuGgYbUgGy'
+        self.push('334 QnVHZ1liVWdHeQ==')
+
+    def _auth_cram_md5(self, arg=None):
+        if arg is None:
+            self.push('334 {}'.format(sim_cram_md5_challenge))
+        else:
+            logpass = self._decode_base64(arg)
+            try:
+                user, hashed_pass = logpass.split()
+            except ValueError as e:
+                self.push('535 Splitting response {!r} into user and password '
+                          'failed: {}'.format(logpass, e))
+                return False
+            valid_hashed_pass = hmac.HMAC(
+                sim_auth[1].encode('ascii'),
+                self._decode_base64(sim_cram_md5_challenge).encode('ascii'),
+                'md5').hexdigest()
+            self._authenticated(user, hashed_pass == valid_hashed_pass)
+    # end AUTH related stuff.
+
+    def smtp_EHLO(self, arg):
+        resp = ('250-testhost\r\n'
+                '250-EXPN\r\n'
+                '250-SIZE 20000000\r\n'
+                '250-STARTTLS\r\n'
+                '250-DELIVERBY\r\n')
+        resp = resp + self._extrafeatures + '250 HELP'
+        self.push(resp)
+        self.seen_greeting = arg
+        self.extended_smtp = True
+
+    def smtp_VRFY(self, arg):
+        # For max compatibility smtplib should be sending the raw address.
+        if arg in sim_users:
+            self.push('250 %s %s' % (sim_users[arg], smtplib.quoteaddr(arg)))
+        else:
+            self.push('550 No such user: %s' % arg)
+
+    def smtp_EXPN(self, arg):
+        list_name = arg.lower()
+        if list_name in sim_lists:
+            user_list = sim_lists[list_name]
+            for n, user_email in enumerate(user_list):
+                quoted_addr = smtplib.quoteaddr(user_email)
+                if n < len(user_list) - 1:
+                    self.push('250-%s %s' % (sim_users[user_email], quoted_addr))
+                else:
+                    self.push('250 %s %s' % (sim_users[user_email], quoted_addr))
+        else:
+            self.push('550 No access for you!')
+
+    def smtp_QUIT(self, arg):
+        if self.quit_response is None:
+            super(SimSMTPChannel, self).smtp_QUIT(arg)
+        else:
+            self.push(self.quit_response)
+            self.close_when_done()
+
+    def smtp_MAIL(self, arg):
+        if self.mail_response is None:
+            super().smtp_MAIL(arg)
+        else:
+            self.push(self.mail_response)
+            if self.disconnect:
+                self.close_when_done()
+
+    def smtp_RCPT(self, arg):
+        if self.rcpt_response is None:
+            super().smtp_RCPT(arg)
+            return
+        self.rcpt_count += 1
+        self.push(self.rcpt_response[self.rcpt_count-1])
+
+    def smtp_RSET(self, arg):
+        self.rset_count += 1
+        super().smtp_RSET(arg)
+
+    def smtp_DATA(self, arg):
+        if self.data_response is None:
+            super().smtp_DATA(arg)
+        else:
+            self.push(self.data_response)
+
+    def handle_error(self):
+        raise
+
+
+class SimSMTPServer(smtpd.SMTPServer):
+
+    channel_class = SimSMTPChannel
+
+    def __init__(self, *args, **kw):
+        self._extra_features = []
+        self._addresses = {}
+        smtpd.SMTPServer.__init__(self, *args, **kw)
+
+    def handle_accepted(self, conn, addr):
+        self._SMTPchannel = self.channel_class(
+            self._extra_features, self, conn, addr,
+            decode_data=self._decode_data)
+
+    def process_message(self, peer, mailfrom, rcpttos, data):
+        self._addresses['from'] = mailfrom
+        self._addresses['tos'] = rcpttos
+
+    def add_feature(self, feature):
+        self._extra_features.append(feature)
+
+    def handle_error(self):
+        raise
+
+
+# Test various SMTP & ESMTP commands/behaviors that require a simulated server
+# (i.e., something with more features than DebuggingServer)
+class SMTPSimTests(unittest.TestCase):
+
+    def setUp(self):
+        self.thread_key = threading_helper.threading_setup()
+        self.real_getfqdn = socket.getfqdn
+        socket.getfqdn = mock_socket.getfqdn
+        self.serv_evt = threading.Event()
+        self.client_evt = threading.Event()
+        # Pick a random unused port by passing 0 for the port number
+        self.serv = SimSMTPServer((HOST, 0), ('nowhere', -1), decode_data=True)
+        # Keep a note of what port was assigned
+        self.port = self.serv.socket.getsockname()[1]
+        serv_args = (self.serv, self.serv_evt, self.client_evt)
+        self.thread = threading.Thread(target=debugging_server, args=serv_args)
+        self.thread.start()
+
+        # wait until server thread has assigned a port number
+        self.serv_evt.wait()
+        self.serv_evt.clear()
+
+    def tearDown(self):
+        socket.getfqdn = self.real_getfqdn
+        # indicate that the client is finished
+        self.client_evt.set()
+        # wait for the server thread to terminate
+        self.serv_evt.wait()
+        threading_helper.join_thread(self.thread)
+        del self.thread
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self.thread_key)
+
+    def testBasic(self):
+        # smoke test
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.quit()
+
+    def testEHLO(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+
+        # no features should be present before the EHLO
+        self.assertEqual(smtp.esmtp_features, {})
+
+        # features expected from the test server
+        expected_features = {'expn':'',
+                             'size': '20000000',
+                             'starttls': '',
+                             'deliverby': '',
+                             'help': '',
+                             }
+
+        smtp.ehlo()
+        self.assertEqual(smtp.esmtp_features, expected_features)
+        for k in expected_features:
+            self.assertTrue(smtp.has_extn(k))
+        self.assertFalse(smtp.has_extn('unsupported-feature'))
+        smtp.quit()
+
+    def testVRFY(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+
+        for addr_spec, name in sim_users.items():
+            expected_known = (250, bytes('%s %s' %
+                                         (name, smtplib.quoteaddr(addr_spec)),
+                                         "ascii"))
+            self.assertEqual(smtp.vrfy(addr_spec), expected_known)
+
+        u = 'nobody@nowhere.com'
+        expected_unknown = (550, ('No such user: %s' % u).encode('ascii'))
+        self.assertEqual(smtp.vrfy(u), expected_unknown)
+        smtp.quit()
+
+    def testEXPN(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+
+        for listname, members in sim_lists.items():
+            users = []
+            for m in members:
+                users.append('%s %s' % (sim_users[m], smtplib.quoteaddr(m)))
+            expected_known = (250, bytes('\n'.join(users), "ascii"))
+            self.assertEqual(smtp.expn(listname), expected_known)
+
+        u = 'PSU-Members-List'
+        expected_unknown = (550, b'No access for you!')
+        self.assertEqual(smtp.expn(u), expected_unknown)
+        smtp.quit()
+
+    def testAUTH_PLAIN(self):
+        self.serv.add_feature("AUTH PLAIN")
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        resp = smtp.login(sim_auth[0], sim_auth[1])
+        self.assertEqual(resp, (235, b'Authentication Succeeded'))
+        smtp.close()
+
+    def testAUTH_LOGIN(self):
+        self.serv.add_feature("AUTH LOGIN")
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        resp = smtp.login(sim_auth[0], sim_auth[1])
+        self.assertEqual(resp, (235, b'Authentication Succeeded'))
+        smtp.close()
+
+    def testAUTH_LOGIN_initial_response_ok(self):
+        self.serv.add_feature("AUTH LOGIN")
+        with smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                          timeout=support.LOOPBACK_TIMEOUT) as smtp:
+            smtp.user, smtp.password = sim_auth
+            smtp.ehlo("test_auth_login")
+            resp = smtp.auth("LOGIN", smtp.auth_login, initial_response_ok=True)
+            self.assertEqual(resp, (235, b'Authentication Succeeded'))
+
+    def testAUTH_LOGIN_initial_response_notok(self):
+        self.serv.add_feature("AUTH LOGIN")
+        with smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                          timeout=support.LOOPBACK_TIMEOUT) as smtp:
+            smtp.user, smtp.password = sim_auth
+            smtp.ehlo("test_auth_login")
+            resp = smtp.auth("LOGIN", smtp.auth_login, initial_response_ok=False)
+            self.assertEqual(resp, (235, b'Authentication Succeeded'))
+
+    def testAUTH_BUGGY(self):
+        self.serv.add_feature("AUTH BUGGY")
+
+        def auth_buggy(challenge=None):
+            self.assertEqual(b"BuGgYbUgGy", challenge)
+            return "\0"
+
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT
+        )
+        try:
+            smtp.user, smtp.password = sim_auth
+            smtp.ehlo("test_auth_buggy")
+            expect = r"^Server AUTH mechanism infinite loop.*"
+            with self.assertRaisesRegex(smtplib.SMTPException, expect) as cm:
+                smtp.auth("BUGGY", auth_buggy, initial_response_ok=False)
+        finally:
+            smtp.close()
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    @hashlib_helper.requires_hashdigest('md5', openssl=True)
+    def testAUTH_CRAM_MD5(self):
+        self.serv.add_feature("AUTH CRAM-MD5")
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        resp = smtp.login(sim_auth[0], sim_auth[1])
+        self.assertEqual(resp, (235, b'Authentication Succeeded'))
+        smtp.close()
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    @hashlib_helper.requires_hashdigest('md5', openssl=True)
+    def testAUTH_multiple(self):
+        # Test that multiple authentication methods are tried.
+        self.serv.add_feature("AUTH BOGUS PLAIN LOGIN CRAM-MD5")
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        resp = smtp.login(sim_auth[0], sim_auth[1])
+        self.assertEqual(resp, (235, b'Authentication Succeeded'))
+        smtp.close()
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_auth_function(self):
+        supported = {'PLAIN', 'LOGIN'}
+        try:
+            hashlib.md5()
+        except ValueError:
+            pass
+        else:
+            supported.add('CRAM-MD5')
+        for mechanism in supported:
+            self.serv.add_feature("AUTH {}".format(mechanism))
+        for mechanism in supported:
+            with self.subTest(mechanism=mechanism):
+                smtp = smtplib.SMTP(HOST, self.port,
+                                    local_hostname='localhost',
+                                    timeout=support.LOOPBACK_TIMEOUT)
+                smtp.ehlo('foo')
+                smtp.user, smtp.password = sim_auth[0], sim_auth[1]
+                method = 'auth_' + mechanism.lower().replace('-', '_')
+                resp = smtp.auth(mechanism, getattr(smtp, method))
+                self.assertEqual(resp, (235, b'Authentication Succeeded'))
+                smtp.close()
+
+    def test_quit_resets_greeting(self):
+        smtp = smtplib.SMTP(HOST, self.port,
+                            local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        code, message = smtp.ehlo()
+        self.assertEqual(code, 250)
+        self.assertIn('size', smtp.esmtp_features)
+        smtp.quit()
+        self.assertNotIn('size', smtp.esmtp_features)
+        smtp.connect(HOST, self.port)
+        self.assertNotIn('size', smtp.esmtp_features)
+        smtp.ehlo_or_helo_if_needed()
+        self.assertIn('size', smtp.esmtp_features)
+        smtp.quit()
+
+    def test_with_statement(self):
+        with smtplib.SMTP(HOST, self.port) as smtp:
+            code, message = smtp.noop()
+            self.assertEqual(code, 250)
+        self.assertRaises(smtplib.SMTPServerDisconnected, smtp.send, b'foo')
+        with smtplib.SMTP(HOST, self.port) as smtp:
+            smtp.close()
+        self.assertRaises(smtplib.SMTPServerDisconnected, smtp.send, b'foo')
+
+    def test_with_statement_QUIT_failure(self):
+        with self.assertRaises(smtplib.SMTPResponseException) as error:
+            with smtplib.SMTP(HOST, self.port) as smtp:
+                smtp.noop()
+                self.serv._SMTPchannel.quit_response = '421 QUIT FAILED'
+        self.assertEqual(error.exception.smtp_code, 421)
+        self.assertEqual(error.exception.smtp_error, b'QUIT FAILED')
+
+    #TODO: add tests for correct AUTH method fallback now that the
+    #test infrastructure can support it.
+
+    # Issue 17498: make sure _rset does not raise SMTPServerDisconnected exception
+    def test__rest_from_mail_cmd(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.noop()
+        self.serv._SMTPchannel.mail_response = '451 Requested action aborted'
+        self.serv._SMTPchannel.disconnect = True
+        with self.assertRaises(smtplib.SMTPSenderRefused):
+            smtp.sendmail('John', 'Sally', 'test message')
+        self.assertIsNone(smtp.sock)
+
+    # Issue 5713: make sure close, not rset, is called if we get a 421 error
+    def test_421_from_mail_cmd(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.noop()
+        self.serv._SMTPchannel.mail_response = '421 closing connection'
+        with self.assertRaises(smtplib.SMTPSenderRefused):
+            smtp.sendmail('John', 'Sally', 'test message')
+        self.assertIsNone(smtp.sock)
+        self.assertEqual(self.serv._SMTPchannel.rset_count, 0)
+
+    def test_421_from_rcpt_cmd(self):
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.noop()
+        self.serv._SMTPchannel.rcpt_response = ['250 accepted', '421 closing']
+        with self.assertRaises(smtplib.SMTPRecipientsRefused) as r:
+            smtp.sendmail('John', ['Sally', 'Frank', 'George'], 'test message')
+        self.assertIsNone(smtp.sock)
+        self.assertEqual(self.serv._SMTPchannel.rset_count, 0)
+        self.assertDictEqual(r.exception.args[0], {'Frank': (421, b'closing')})
+
+    def test_421_from_data_cmd(self):
+        class MySimSMTPChannel(SimSMTPChannel):
+            def found_terminator(self):
+                if self.smtp_state == self.DATA:
+                    self.push('421 closing')
+                else:
+                    super().found_terminator()
+        self.serv.channel_class = MySimSMTPChannel
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.noop()
+        with self.assertRaises(smtplib.SMTPDataError):
+            smtp.sendmail('John@foo.org', ['Sally@foo.org'], 'test message')
+        self.assertIsNone(smtp.sock)
+        self.assertEqual(self.serv._SMTPchannel.rcpt_count, 0)
+
+    def test_smtputf8_NotSupportedError_if_no_server_support(self):
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.ehlo()
+        self.assertTrue(smtp.does_esmtp)
+        self.assertFalse(smtp.has_extn('smtputf8'))
+        self.assertRaises(
+            smtplib.SMTPNotSupportedError,
+            smtp.sendmail,
+            'John', 'Sally', '', mail_options=['BODY=8BITMIME', 'SMTPUTF8'])
+        self.assertRaises(
+            smtplib.SMTPNotSupportedError,
+            smtp.mail, 'John', options=['BODY=8BITMIME', 'SMTPUTF8'])
+
+    def test_send_unicode_without_SMTPUTF8(self):
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        self.assertRaises(UnicodeEncodeError, smtp.sendmail, 'Alice', 'Böb', '')
+        self.assertRaises(UnicodeEncodeError, smtp.mail, 'Älice')
+
+    def test_send_message_error_on_non_ascii_addrs_if_no_smtputf8(self):
+        # This test is located here and not in the SMTPUTF8SimTests
+        # class because it needs a "regular" SMTP server to work
+        msg = EmailMessage()
+        msg['From'] = "Páolo <főo@bar.com>"
+        msg['To'] = 'Dinsdale'
+        msg['Subject'] = 'Nudge nudge, wink, wink \u1F609'
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        with self.assertRaises(smtplib.SMTPNotSupportedError):
+            smtp.send_message(msg)
+
+    def test_name_field_not_included_in_envelop_addresses(self):
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+
+        message = EmailMessage()
+        message['From'] = email.utils.formataddr(('Michaël', 'michael@example.com'))
+        message['To'] = email.utils.formataddr(('René', 'rene@example.com'))
+
+        self.assertDictEqual(smtp.send_message(message), {})
+
+        self.assertEqual(self.serv._addresses['from'], 'michael@example.com')
+        self.assertEqual(self.serv._addresses['tos'], ['rene@example.com'])
+
+
+class SimSMTPUTF8Server(SimSMTPServer):
+
+    def __init__(self, *args, **kw):
+        # The base SMTP server turns these on automatically, but our test
+        # server is set up to munge the EHLO response, so we need to provide
+        # them as well.  And yes, the call is to SMTPServer not SimSMTPServer.
+        self._extra_features = ['SMTPUTF8', '8BITMIME']
+        smtpd.SMTPServer.__init__(self, *args, **kw)
+
+    def handle_accepted(self, conn, addr):
+        self._SMTPchannel = self.channel_class(
+            self._extra_features, self, conn, addr,
+            decode_data=self._decode_data,
+            enable_SMTPUTF8=self.enable_SMTPUTF8,
+        )
+
+    def process_message(self, peer, mailfrom, rcpttos, data, mail_options=None,
+                        rcpt_options=None):
+        self.last_peer = peer
+        self.last_mailfrom = mailfrom
+        self.last_rcpttos = rcpttos
+        self.last_message = data
+        self.last_mail_options = mail_options
+        self.last_rcpt_options = rcpt_options
+
+
+class SMTPUTF8SimTests(unittest.TestCase):
+
+    maxDiff = None
+
+    def setUp(self):
+        self.thread_key = threading_helper.threading_setup()
+        self.real_getfqdn = socket.getfqdn
+        socket.getfqdn = mock_socket.getfqdn
+        self.serv_evt = threading.Event()
+        self.client_evt = threading.Event()
+        # Pick a random unused port by passing 0 for the port number
+        self.serv = SimSMTPUTF8Server((HOST, 0), ('nowhere', -1),
+                                      decode_data=False,
+                                      enable_SMTPUTF8=True)
+        # Keep a note of what port was assigned
+        self.port = self.serv.socket.getsockname()[1]
+        serv_args = (self.serv, self.serv_evt, self.client_evt)
+        self.thread = threading.Thread(target=debugging_server, args=serv_args)
+        self.thread.start()
+
+        # wait until server thread has assigned a port number
+        self.serv_evt.wait()
+        self.serv_evt.clear()
+
+    def tearDown(self):
+        socket.getfqdn = self.real_getfqdn
+        # indicate that the client is finished
+        self.client_evt.set()
+        # wait for the server thread to terminate
+        self.serv_evt.wait()
+        threading_helper.join_thread(self.thread)
+        del self.thread
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self.thread_key)
+
+    def test_test_server_supports_extensions(self):
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.ehlo()
+        self.assertTrue(smtp.does_esmtp)
+        self.assertTrue(smtp.has_extn('smtputf8'))
+
+    def test_send_unicode_with_SMTPUTF8_via_sendmail(self):
+        m = '¡a test message containing unicode!'.encode('utf-8')
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.sendmail('Jőhn', 'Sálly', m,
+                      mail_options=['BODY=8BITMIME', 'SMTPUTF8'])
+        self.assertEqual(self.serv.last_mailfrom, 'Jőhn')
+        self.assertEqual(self.serv.last_rcpttos, ['Sálly'])
+        self.assertEqual(self.serv.last_message, m)
+        self.assertIn('BODY=8BITMIME', self.serv.last_mail_options)
+        self.assertIn('SMTPUTF8', self.serv.last_mail_options)
+        self.assertEqual(self.serv.last_rcpt_options, [])
+
+    def test_send_unicode_with_SMTPUTF8_via_low_level_API(self):
+        m = '¡a test message containing unicode!'.encode('utf-8')
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        smtp.ehlo()
+        self.assertEqual(
+            smtp.mail('Jő', options=['BODY=8BITMIME', 'SMTPUTF8']),
+            (250, b'OK'))
+        self.assertEqual(smtp.rcpt('János'), (250, b'OK'))
+        self.assertEqual(smtp.data(m), (250, b'OK'))
+        self.assertEqual(self.serv.last_mailfrom, 'Jő')
+        self.assertEqual(self.serv.last_rcpttos, ['János'])
+        self.assertEqual(self.serv.last_message, m)
+        self.assertIn('BODY=8BITMIME', self.serv.last_mail_options)
+        self.assertIn('SMTPUTF8', self.serv.last_mail_options)
+        self.assertEqual(self.serv.last_rcpt_options, [])
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_send_message_uses_smtputf8_if_addrs_non_ascii(self):
+        msg = EmailMessage()
+        msg['From'] = "Páolo <főo@bar.com>"
+        msg['To'] = 'Dinsdale'
+        msg['Subject'] = 'Nudge nudge, wink, wink \u1F609'
+        # XXX I don't know why I need two \n's here, but this is an existing
+        # bug (if it is one) and not a problem with the new functionality.
+        msg.set_content("oh là là, know what I mean, know what I mean?\n\n")
+        # XXX smtpd converts received /r/n to /n, so we can't easily test that
+        # we are successfully sending /r/n :(.
+        expected = textwrap.dedent("""\
+            From: Páolo <főo@bar.com>
+            To: Dinsdale
+            Subject: Nudge nudge, wink, wink \u1F609
+            Content-Type: text/plain; charset="utf-8"
+            Content-Transfer-Encoding: 8bit
+            MIME-Version: 1.0
+
+            oh là là, know what I mean, know what I mean?
+            """)
+        smtp = smtplib.SMTP(
+            HOST, self.port, local_hostname='localhost',
+            timeout=support.LOOPBACK_TIMEOUT)
+        self.addCleanup(smtp.close)
+        self.assertEqual(smtp.send_message(msg), {})
+        self.assertEqual(self.serv.last_mailfrom, 'főo@bar.com')
+        self.assertEqual(self.serv.last_rcpttos, ['Dinsdale'])
+        self.assertEqual(self.serv.last_message.decode(), expected)
+        self.assertIn('BODY=8BITMIME', self.serv.last_mail_options)
+        self.assertIn('SMTPUTF8', self.serv.last_mail_options)
+        self.assertEqual(self.serv.last_rcpt_options, [])
+
+
+EXPECTED_RESPONSE = encode_base64(b'\0psu\0doesnotexist', eol='')
+
+class SimSMTPAUTHInitialResponseChannel(SimSMTPChannel):
+    def smtp_AUTH(self, arg):
+        # RFC 4954's AUTH command allows for an optional initial-response.
+        # Not all AUTH methods support this; some require a challenge.  AUTH
+        # PLAIN does those, so test that here.  See issue #15014.
+        args = arg.split()
+        if args[0].lower() == 'plain':
+            if len(args) == 2:
+                # AUTH PLAIN <initial-response> with the response base 64
+                # encoded.  Hard code the expected response for the test.
+                if args[1] == EXPECTED_RESPONSE:
+                    self.push('235 Ok')
+                    return
+        self.push('571 Bad authentication')
+
+class SimSMTPAUTHInitialResponseServer(SimSMTPServer):
+    channel_class = SimSMTPAUTHInitialResponseChannel
+
+
+class SMTPAUTHInitialResponseSimTests(unittest.TestCase):
+    def setUp(self):
+        self.thread_key = threading_helper.threading_setup()
+        self.real_getfqdn = socket.getfqdn
+        socket.getfqdn = mock_socket.getfqdn
+        self.serv_evt = threading.Event()
+        self.client_evt = threading.Event()
+        # Pick a random unused port by passing 0 for the port number
+        self.serv = SimSMTPAUTHInitialResponseServer(
+            (HOST, 0), ('nowhere', -1), decode_data=True)
+        # Keep a note of what port was assigned
+        self.port = self.serv.socket.getsockname()[1]
+        serv_args = (self.serv, self.serv_evt, self.client_evt)
+        self.thread = threading.Thread(target=debugging_server, args=serv_args)
+        self.thread.start()
+
+        # wait until server thread has assigned a port number
+        self.serv_evt.wait()
+        self.serv_evt.clear()
+
+    def tearDown(self):
+        socket.getfqdn = self.real_getfqdn
+        # indicate that the client is finished
+        self.client_evt.set()
+        # wait for the server thread to terminate
+        self.serv_evt.wait()
+        threading_helper.join_thread(self.thread)
+        del self.thread
+        self.doCleanups()
+        threading_helper.threading_cleanup(*self.thread_key)
+
+    def testAUTH_PLAIN_initial_response_login(self):
+        self.serv.add_feature('AUTH PLAIN')
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.login('psu', 'doesnotexist')
+        smtp.close()
+
+    def testAUTH_PLAIN_initial_response_auth(self):
+        self.serv.add_feature('AUTH PLAIN')
+        smtp = smtplib.SMTP(HOST, self.port, local_hostname='localhost',
+                            timeout=support.LOOPBACK_TIMEOUT)
+        smtp.user = 'psu'
+        smtp.password = 'doesnotexist'
+        code, response = smtp.auth('plain', smtp.auth_plain)
+        smtp.close()
+        self.assertEqual(code, 235)
+
+
+if __name__ == '__main__':
+    unittest.main()
diff --git a/Lib/test/test_smtpnet.py b/Lib/test/test_smtpnet.py
new file mode 100644
index 0000000000..be25e961f7
--- /dev/null
+++ b/Lib/test/test_smtpnet.py
@@ -0,0 +1,90 @@
+import unittest
+from test import support
+from test.support import import_helper
+from test.support import socket_helper
+import smtplib
+import socket
+
+ssl = import_helper.import_module("ssl")
+
+support.requires("network")
+
+def check_ssl_verifiy(host, port):
+    context = ssl.create_default_context()
+    with socket.create_connection((host, port)) as sock:
+        try:
+            sock = context.wrap_socket(sock, server_hostname=host)
+        except Exception:
+            return False
+        else:
+            sock.close()
+            return True
+
+
+class SmtpTest(unittest.TestCase):
+    testServer = 'smtp.gmail.com'
+    remotePort = 587
+
+    def test_connect_starttls(self):
+        support.get_attribute(smtplib, 'SMTP_SSL')
+        context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
+        context.check_hostname = False
+        context.verify_mode = ssl.CERT_NONE
+        with socket_helper.transient_internet(self.testServer):
+            server = smtplib.SMTP(self.testServer, self.remotePort)
+            try:
+                server.starttls(context=context)
+            except smtplib.SMTPException as e:
+                if e.args[0] == 'STARTTLS extension not supported by server.':
+                    unittest.skip(e.args[0])
+                else:
+                    raise
+            server.ehlo()
+            server.quit()
+
+
+class SmtpSSLTest(unittest.TestCase):
+    testServer = 'smtp.gmail.com'
+    remotePort = 465
+
+    def test_connect(self):
+        support.get_attribute(smtplib, 'SMTP_SSL')
+        with socket_helper.transient_internet(self.testServer):
+            server = smtplib.SMTP_SSL(self.testServer, self.remotePort)
+            server.ehlo()
+            server.quit()
+
+    def test_connect_default_port(self):
+        support.get_attribute(smtplib, 'SMTP_SSL')
+        with socket_helper.transient_internet(self.testServer):
+            server = smtplib.SMTP_SSL(self.testServer)
+            server.ehlo()
+            server.quit()
+
+    @support.requires_resource('walltime')
+    def test_connect_using_sslcontext(self):
+        context = ssl.SSLContext(ssl.PROTOCOL_TLS_CLIENT)
+        context.check_hostname = False
+        context.verify_mode = ssl.CERT_NONE
+        support.get_attribute(smtplib, 'SMTP_SSL')
+        with socket_helper.transient_internet(self.testServer):
+            server = smtplib.SMTP_SSL(self.testServer, self.remotePort, context=context)
+            server.ehlo()
+            server.quit()
+
+    def test_connect_using_sslcontext_verified(self):
+        with socket_helper.transient_internet(self.testServer):
+            can_verify = check_ssl_verifiy(self.testServer, self.remotePort)
+            if not can_verify:
+                self.skipTest("SSL certificate can't be verified")
+
+        support.get_attribute(smtplib, 'SMTP_SSL')
+        context = ssl.create_default_context()
+        with socket_helper.transient_internet(self.testServer):
+            server = smtplib.SMTP_SSL(self.testServer, self.remotePort, context=context)
+            server.ehlo()
+            server.quit()
+
+
+if __name__ == "__main__":
+    unittest.main()
\ No newline at end of file
diff --git a/Lib/test/test_tokenize.py b/Lib/test/test_tokenize.py
index e2d2f89454..44ef4e2416 100644
--- a/Lib/test/test_tokenize.py
+++ b/Lib/test/test_tokenize.py
@@ -1237,7 +1237,6 @@ def test_utf8_normalization(self):
                 found, consumed_lines = detect_encoding(rl)
                 self.assertEqual(found, "utf-8")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_short_files(self):
         readline = self.get_readline((b'print(something)\n',))
         encoding, consumed_lines = detect_encoding(readline)
@@ -1316,7 +1315,6 @@ def readline(self):
             ins = Bunk(lines, path)
             detect_encoding(ins.readline)
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_open_error(self):
         # Issue #23840: open() must close the binary file on error
         m = BytesIO(b'#coding:xxx')
diff --git a/Lib/test/test_unary.py b/Lib/test/test_unary.py
index c3c17cc9f6..a45fbf6bd6 100644
--- a/Lib/test/test_unary.py
+++ b/Lib/test/test_unary.py
@@ -8,7 +8,6 @@ def test_negative(self):
         self.assertTrue(-2 == 0 - 2)
         self.assertEqual(-0, 0)
         self.assertEqual(--2, 2)
-        self.assertTrue(-2 == 0 - 2)
         self.assertTrue(-2.0 == 0 - 2.0)
         self.assertTrue(-2j == 0 - 2j)
 
@@ -16,15 +15,13 @@ def test_positive(self):
         self.assertEqual(+2, 2)
         self.assertEqual(+0, 0)
         self.assertEqual(++2, 2)
-        self.assertEqual(+2, 2)
         self.assertEqual(+2.0, 2.0)
         self.assertEqual(+2j, 2j)
 
     def test_invert(self):
-        self.assertTrue(-2 == 0 - 2)
-        self.assertEqual(-0, 0)
-        self.assertEqual(--2, 2)
-        self.assertTrue(-2 == 0 - 2)
+        self.assertTrue(~2 == -(2+1))
+        self.assertEqual(~0, -1)
+        self.assertEqual(~~2, 2)
 
     def test_no_overflow(self):
         nines = "9" * 32
diff --git a/Lib/test/test_zlib.py b/Lib/test/test_zlib.py
index 686131be74..0a75457ad8 100644
--- a/Lib/test/test_zlib.py
+++ b/Lib/test/test_zlib.py
@@ -20,18 +20,18 @@
     'requires Decompress.copy()')
 
 
-# def _zlib_runtime_version_tuple(zlib_version=zlib.ZLIB_RUNTIME_VERSION):
-#     # Register "1.2.3" as "1.2.3.0"
-#     # or "1.2.0-linux","1.2.0.f","1.2.0.f-linux"
-#     v = zlib_version.split('-', 1)[0].split('.')
-#     if len(v) < 4:
-#         v.append('0')
-#     elif not v[-1].isnumeric():
-#         v[-1] = '0'
-#     return tuple(map(int, v))
-#
-#
-# ZLIB_RUNTIME_VERSION_TUPLE = _zlib_runtime_version_tuple()
+def _zlib_runtime_version_tuple(zlib_version=zlib.ZLIB_RUNTIME_VERSION):
+    # Register "1.2.3" as "1.2.3.0"
+    # or "1.2.0-linux","1.2.0.f","1.2.0.f-linux"
+    v = zlib_version.split('-', 1)[0].split('.')
+    if len(v) < 4:
+        v.append('0')
+    elif not v[-1].isnumeric():
+        v[-1] = '0'
+    return tuple(map(int, v))
+
+
+ZLIB_RUNTIME_VERSION_TUPLE = _zlib_runtime_version_tuple()
 
 
 # bpo-46623: When a hardware accelerator is used (currently only on s390x),
@@ -66,8 +66,6 @@
 
 class VersionTestCase(unittest.TestCase):
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_library_version(self):
         # Test that the major version of the actual library in use matches the
         # major version that we were compiled against. We can't guarantee that
@@ -282,8 +280,6 @@ def test_64bit_compress(self, size):
 
 
 class CompressObjectTestCase(BaseCompressTestCase, unittest.TestCase):
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     # Test compression object
     def test_pair(self):
         # straightforward compress/decompress objects
@@ -307,8 +303,6 @@ def test_pair(self):
             self.assertIsInstance(dco.unconsumed_tail, bytes)
             self.assertIsInstance(dco.unused_data, bytes)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_keywords(self):
         level = 2
         method = zlib.DEFLATED
@@ -466,8 +460,6 @@ def test_decompressmaxlen(self, flush=False):
     def test_decompressmaxlenflush(self):
         self.test_decompressmaxlen(flush=True)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_maxlenmisc(self):
         # Misc tests of max_length
         dco = zlib.decompressobj()
@@ -498,7 +490,7 @@ def test_clear_unconsumed_tail(self):
         ddata += dco.decompress(dco.unconsumed_tail)
         self.assertEqual(dco.unconsumed_tail, b"")
 
-    # TODO: RUSTPYTHON
+    # TODO: RUSTPYTHON: Z_BLOCK support in flate2
     @unittest.expectedFailure
     def test_flushes(self):
         # Test flush() with the various options, using all the
@@ -560,8 +552,6 @@ def test_empty_flush(self):
         dco = zlib.decompressobj()
         self.assertEqual(dco.flush(), b"") # Returns nothing
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_dictionary(self):
         h = HAMLET_SCENE
         # Build a simulated dictionary out of the words in HAMLET.
@@ -578,8 +568,6 @@ def test_dictionary(self):
         dco = zlib.decompressobj()
         self.assertRaises(zlib.error, dco.decompress, cd)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_dictionary_streaming(self):
         # This simulates the reuse of a compressor object for compressing
         # several separate data streams.
@@ -652,8 +640,6 @@ def test_decompress_unused_data(self):
                 self.assertEqual(dco.unconsumed_tail, b'')
                 self.assertEqual(dco.unused_data, remainder)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     # issue27164
     def test_decompress_raw_with_dictionary(self):
         zdict = b'abcdefghijklmnopqrstuvwxyz'
@@ -829,7 +815,7 @@ def test_large_unconsumed_tail(self, size):
         finally:
             comp = uncomp = data = None
 
-    # TODO: RUSTPYTHON
+    # TODO: RUSTPYTHON: wbits=0 support in flate2
     @unittest.expectedFailure
     def test_wbits(self):
         # wbits=0 only supported since zlib v1.2.3.5
@@ -997,8 +983,6 @@ def testDecompressUnusedData(self):
         self.assertEqual(text, self.TEXT)
         self.assertEqual(zlibd.unused_data, unused_data)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def testEOFError(self):
         zlibd = zlib._ZlibDecompressor()
         text = zlibd.decompress(self.DATA)
@@ -1029,8 +1013,6 @@ def testPickle(self):
             with self.assertRaises(TypeError):
                 pickle.dumps(zlib._ZlibDecompressor(), proto)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def testDecompressorChunksMaxsize(self):
         zlibd = zlib._ZlibDecompressor()
         max_length = 100
@@ -1062,8 +1044,6 @@ def testDecompressorChunksMaxsize(self):
         self.assertEqual(out, self.BIG_TEXT)
         self.assertEqual(zlibd.unused_data, b"")
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decompressor_inputbuf_1(self):
         # Test reusing input buffer after moving existing
         # contents to beginning
@@ -1086,8 +1066,6 @@ def test_decompressor_inputbuf_1(self):
         out.append(zlibd.decompress(self.DATA[105:]))
         self.assertEqual(b''.join(out), self.TEXT)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decompressor_inputbuf_2(self):
         # Test reusing input buffer by appending data at the
         # end right away
@@ -1109,8 +1087,6 @@ def test_decompressor_inputbuf_2(self):
         out.append(zlibd.decompress(self.DATA[300:]))
         self.assertEqual(b''.join(out), self.TEXT)
 
-    # TODO: RUSTPYTHON
-    @unittest.expectedFailure
     def test_decompressor_inputbuf_3(self):
         # Test reusing input buffer after extending it
 
diff --git a/README.md b/README.md
index 5b5b16d566..38e4d8fa8c 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 # [RustPython](https://rustpython.github.io/)
 
-A Python-3 (CPython >= 3.12.0) Interpreter written in Rust :snake: :scream:
+A Python-3 (CPython >= 3.13.0) Interpreter written in Rust :snake: :scream:
 :metal:.
 
 [![Build Status](https://github.com/RustPython/RustPython/workflows/CI/badge.svg)](https://github.com/RustPython/RustPython/actions?query=workflow%3ACI)
diff --git a/benches/execution.rs b/benches/execution.rs
index 6ec9b89f2a..57529bbb3a 100644
--- a/benches/execution.rs
+++ b/benches/execution.rs
@@ -1,11 +1,11 @@
 use criterion::measurement::WallTime;
 use criterion::{
-    black_box, criterion_group, criterion_main, Bencher, BenchmarkGroup, BenchmarkId, Criterion,
-    Throughput,
+    Bencher, BenchmarkGroup, BenchmarkId, Criterion, Throughput, black_box, criterion_group,
+    criterion_main,
 };
 use rustpython_compiler::Mode;
-use rustpython_parser::ast;
 use rustpython_parser::Parse;
+use rustpython_parser::ast;
 use rustpython_vm::{Interpreter, PyResult, Settings};
 use std::collections::HashMap;
 use std::path::Path;
diff --git a/benches/microbenchmarks.rs b/benches/microbenchmarks.rs
index b742b959b7..6f41f00d6c 100644
--- a/benches/microbenchmarks.rs
+++ b/benches/microbenchmarks.rs
@@ -1,6 +1,6 @@
 use criterion::{
-    criterion_group, criterion_main, measurement::WallTime, BatchSize, BenchmarkGroup, BenchmarkId,
-    Criterion, Throughput,
+    BatchSize, BenchmarkGroup, BenchmarkId, Criterion, Throughput, criterion_group, criterion_main,
+    measurement::WallTime,
 };
 use pyo3::types::PyAnyMethods;
 use rustpython_compiler::Mode;
diff --git a/common/src/boxvec.rs b/common/src/boxvec.rs
index 9b73fa0103..3b1f7e90a0 100644
--- a/common/src/boxvec.rs
+++ b/common/src/boxvec.rs
@@ -87,13 +87,16 @@ impl<T> BoxVec<T> {
     pub unsafe fn push_unchecked(&mut self, element: T) {
         let len = self.len();
         debug_assert!(len < self.capacity());
-        ptr::write(self.get_unchecked_ptr(len), element);
-        self.set_len(len + 1);
+        // SAFETY: len < capacity
+        unsafe {
+            ptr::write(self.get_unchecked_ptr(len), element);
+            self.set_len(len + 1);
+        }
     }
 
     /// Get pointer to where element at `index` would be
     unsafe fn get_unchecked_ptr(&mut self, index: usize) -> *mut T {
-        self.xs.as_mut_ptr().add(index).cast()
+        unsafe { self.xs.as_mut_ptr().add(index).cast() }
     }
 
     pub fn insert(&mut self, index: usize, element: T) {
@@ -568,7 +571,7 @@ unsafe fn raw_ptr_add<T>(ptr: *mut T, offset: usize) -> *mut T {
         // Special case for ZST
         (ptr as usize).wrapping_add(offset) as _
     } else {
-        ptr.add(offset)
+        unsafe { ptr.add(offset) }
     }
 }
 
@@ -576,7 +579,7 @@ unsafe fn raw_ptr_write<T>(ptr: *mut T, value: T) {
     if mem::size_of::<T>() == 0 {
         /* nothing */
     } else {
-        ptr::write(ptr, value)
+        unsafe { ptr::write(ptr, value) }
     }
 }
 
diff --git a/common/src/crt_fd.rs b/common/src/crt_fd.rs
index 14f61b8059..64d4df98a5 100644
--- a/common/src/crt_fd.rs
+++ b/common/src/crt_fd.rs
@@ -6,7 +6,7 @@ use std::{cmp, ffi, io};
 #[cfg(windows)]
 use libc::commit as fsync;
 #[cfg(windows)]
-extern "C" {
+unsafe extern "C" {
     #[link_name = "_chsize_s"]
     fn ftruncate(fd: i32, len: i64) -> i32;
 }
@@ -74,7 +74,7 @@ impl Fd {
 
     #[cfg(windows)]
     pub fn to_raw_handle(&self) -> io::Result<std::os::windows::io::RawHandle> {
-        extern "C" {
+        unsafe extern "C" {
             fn _get_osfhandle(fd: i32) -> libc::intptr_t;
         }
         let handle = unsafe { suppress_iph!(_get_osfhandle(self.0)) };
diff --git a/common/src/encodings.rs b/common/src/encodings.rs
index 4e0c1de56a..858d3b8c6b 100644
--- a/common/src/encodings.rs
+++ b/common/src/encodings.rs
@@ -42,8 +42,8 @@ struct DecodeError<'a> {
 /// # Safety
 /// `v[..valid_up_to]` must be valid utf8
 unsafe fn make_decode_err(v: &[u8], valid_up_to: usize, err_len: Option<usize>) -> DecodeError<'_> {
-    let valid_prefix = core::str::from_utf8_unchecked(v.get_unchecked(..valid_up_to));
-    let rest = v.get_unchecked(valid_up_to..);
+    let (valid_prefix, rest) = unsafe { v.split_at_unchecked(valid_up_to) };
+    let valid_prefix = unsafe { core::str::from_utf8_unchecked(valid_prefix) };
     DecodeError {
         valid_prefix,
         rest,
diff --git a/common/src/fileutils.rs b/common/src/fileutils.rs
index dcb78675d8..7d5ff01942 100644
--- a/common/src/fileutils.rs
+++ b/common/src/fileutils.rs
@@ -5,7 +5,7 @@
 pub use libc::stat as StatStruct;
 
 #[cfg(windows)]
-pub use windows::{fstat, StatStruct};
+pub use windows::{StatStruct, fstat};
 
 #[cfg(not(windows))]
 pub fn fstat(fd: libc::c_int) -> std::io::Result<StatStruct> {
@@ -28,19 +28,19 @@ pub mod windows {
     use std::ffi::{CString, OsStr, OsString};
     use std::os::windows::ffi::OsStrExt;
     use std::sync::OnceLock;
-    use windows_sys::core::PCWSTR;
     use windows_sys::Win32::Foundation::{
-        FreeLibrary, SetLastError, BOOL, ERROR_INVALID_HANDLE, ERROR_NOT_SUPPORTED, FILETIME,
-        HANDLE, INVALID_HANDLE_VALUE,
+        BOOL, ERROR_INVALID_HANDLE, ERROR_NOT_SUPPORTED, FILETIME, FreeLibrary, HANDLE,
+        INVALID_HANDLE_VALUE, SetLastError,
     };
     use windows_sys::Win32::Storage::FileSystem::{
-        FileBasicInfo, FileIdInfo, GetFileInformationByHandle, GetFileInformationByHandleEx,
-        GetFileType, BY_HANDLE_FILE_INFORMATION, FILE_ATTRIBUTE_DIRECTORY, FILE_ATTRIBUTE_READONLY,
+        BY_HANDLE_FILE_INFORMATION, FILE_ATTRIBUTE_DIRECTORY, FILE_ATTRIBUTE_READONLY,
         FILE_ATTRIBUTE_REPARSE_POINT, FILE_BASIC_INFO, FILE_ID_INFO, FILE_TYPE_CHAR,
-        FILE_TYPE_DISK, FILE_TYPE_PIPE, FILE_TYPE_UNKNOWN,
+        FILE_TYPE_DISK, FILE_TYPE_PIPE, FILE_TYPE_UNKNOWN, FileBasicInfo, FileIdInfo,
+        GetFileInformationByHandle, GetFileInformationByHandleEx, GetFileType,
     };
     use windows_sys::Win32::System::LibraryLoader::{GetProcAddress, LoadLibraryW};
     use windows_sys::Win32::System::SystemServices::IO_REPARSE_TAG_SYMLINK;
+    use windows_sys::core::PCWSTR;
 
     pub const S_IFIFO: libc::c_int = 0o010000;
     pub const S_IFLNK: libc::c_int = 0o120000;
@@ -94,7 +94,7 @@ pub mod windows {
         }
     }
 
-    extern "C" {
+    unsafe extern "C" {
         fn _get_osfhandle(fd: i32) -> libc::intptr_t;
     }
 
diff --git a/common/src/float_ops.rs b/common/src/float_ops.rs
index 69ae8833a2..46e2d57067 100644
--- a/common/src/float_ops.rs
+++ b/common/src/float_ops.rs
@@ -64,11 +64,7 @@ pub fn gt_int(value: f64, other_int: &BigInt) -> bool {
 }
 
 pub fn div(v1: f64, v2: f64) -> Option<f64> {
-    if v2 != 0.0 {
-        Some(v1 / v2)
-    } else {
-        None
-    }
+    if v2 != 0.0 { Some(v1 / v2) } else { None }
 }
 
 pub fn mod_(v1: f64, v2: f64) -> Option<f64> {
@@ -125,10 +121,69 @@ pub fn nextafter(x: f64, y: f64) -> f64 {
         let b = x.to_bits();
         let bits = if (y > x) == (x > 0.0) { b + 1 } else { b - 1 };
         let ret = f64::from_bits(bits);
-        if ret == 0.0 {
-            ret.copysign(x)
+        if ret == 0.0 { ret.copysign(x) } else { ret }
+    }
+}
+
+#[allow(clippy::float_cmp)]
+pub fn nextafter_with_steps(x: f64, y: f64, steps: u64) -> f64 {
+    if x == y {
+        y
+    } else if x.is_nan() || y.is_nan() {
+        f64::NAN
+    } else if x >= f64::INFINITY {
+        f64::MAX
+    } else if x <= f64::NEG_INFINITY {
+        f64::MIN
+    } else if x == 0.0 {
+        f64::from_bits(1).copysign(y)
+    } else {
+        if steps == 0 {
+            return x;
+        }
+
+        if x.is_nan() {
+            return x;
+        }
+
+        if y.is_nan() {
+            return y;
+        }
+
+        let sign_bit: u64 = 1 << 63;
+
+        let mut ux = x.to_bits();
+        let uy = y.to_bits();
+
+        let ax = ux & !sign_bit;
+        let ay = uy & !sign_bit;
+
+        // If signs are different
+        if ((ux ^ uy) & sign_bit) != 0 {
+            return if ax + ay <= steps {
+                f64::from_bits(uy)
+            } else if ax < steps {
+                let result = (uy & sign_bit) | (steps - ax);
+                f64::from_bits(result)
+            } else {
+                ux -= steps;
+                f64::from_bits(ux)
+            };
+        }
+
+        // If signs are the same
+        if ax > ay {
+            if ax - ay >= steps {
+                ux -= steps;
+                f64::from_bits(ux)
+            } else {
+                f64::from_bits(uy)
+            }
+        } else if ay - ax >= steps {
+            ux += steps;
+            f64::from_bits(ux)
         } else {
-            ret
+            f64::from_bits(uy)
         }
     }
 }
diff --git a/common/src/hash.rs b/common/src/hash.rs
index 4e87eff799..bbc30b1fe1 100644
--- a/common/src/hash.rs
+++ b/common/src/hash.rs
@@ -37,11 +37,11 @@ impl BuildHasher for HashSecret {
     }
 }
 
-impl rand::distributions::Distribution<HashSecret> for rand::distributions::Standard {
+impl rand::distr::Distribution<HashSecret> for rand::distr::StandardUniform {
     fn sample<R: rand::Rng + ?Sized>(&self, rng: &mut R) -> HashSecret {
         HashSecret {
-            k0: rng.gen(),
-            k1: rng.gen(),
+            k0: rng.random(),
+            k1: rng.random(),
         }
     }
 }
@@ -114,7 +114,7 @@ pub fn hash_float(value: f64) -> Option<PyHash> {
     let mut e = frexp.1;
     let mut x: PyUHash = 0;
     while m != 0.0 {
-        x = ((x << 28) & MODULUS) | x >> (BITS - 28);
+        x = ((x << 28) & MODULUS) | (x >> (BITS - 28));
         m *= 268_435_456.0; // 2**28
         e -= 28;
         let y = m as PyUHash; // pull out integer part
@@ -132,7 +132,7 @@ pub fn hash_float(value: f64) -> Option<PyHash> {
     } else {
         BITS32 - 1 - ((-1 - e) % BITS32)
     };
-    x = ((x << e) & MODULUS) | x >> (BITS32 - e);
+    x = ((x << e) & MODULUS) | (x >> (BITS32 - e));
 
     Some(fix_sentinel(x as PyHash * value.signum() as PyHash))
 }
@@ -150,11 +150,7 @@ pub fn hash_bigint(value: &BigInt) -> PyHash {
 
 #[inline(always)]
 pub fn fix_sentinel(x: PyHash) -> PyHash {
-    if x == SENTINEL {
-        -2
-    } else {
-        x
-    }
+    if x == SENTINEL { -2 } else { x }
 }
 
 #[inline]
diff --git a/common/src/int.rs b/common/src/int.rs
index ca449ac708..00b5231dff 100644
--- a/common/src/int.rs
+++ b/common/src/int.rs
@@ -50,7 +50,7 @@ pub fn bytes_to_int(lit: &[u8], mut base: u32) -> Option<BigInt> {
                     base = parsed;
                     true
                 } else {
-                    if let [_first, ref others @ .., last] = lit {
+                    if let [_first, others @ .., last] = lit {
                         let is_zero =
                             others.iter().all(|&c| c == b'0' || c == b'_') && *last == b'0';
                         if !is_zero {
diff --git a/common/src/linked_list.rs b/common/src/linked_list.rs
index 3040bab0b9..7f55d727fb 100644
--- a/common/src/linked_list.rs
+++ b/common/src/linked_list.rs
@@ -208,37 +208,39 @@ impl<L: Link> LinkedList<L, L::Target> {
     /// The caller **must** ensure that `node` is currently contained by
     /// `self` or not contained by any other list.
     pub unsafe fn remove(&mut self, node: NonNull<L::Target>) -> Option<L::Handle> {
-        if let Some(prev) = L::pointers(node).as_ref().get_prev() {
-            debug_assert_eq!(L::pointers(prev).as_ref().get_next(), Some(node));
-            L::pointers(prev)
-                .as_mut()
-                .set_next(L::pointers(node).as_ref().get_next());
-        } else {
-            if self.head != Some(node) {
-                return None;
+        unsafe {
+            if let Some(prev) = L::pointers(node).as_ref().get_prev() {
+                debug_assert_eq!(L::pointers(prev).as_ref().get_next(), Some(node));
+                L::pointers(prev)
+                    .as_mut()
+                    .set_next(L::pointers(node).as_ref().get_next());
+            } else {
+                if self.head != Some(node) {
+                    return None;
+                }
+
+                self.head = L::pointers(node).as_ref().get_next();
             }
 
-            self.head = L::pointers(node).as_ref().get_next();
-        }
+            if let Some(next) = L::pointers(node).as_ref().get_next() {
+                debug_assert_eq!(L::pointers(next).as_ref().get_prev(), Some(node));
+                L::pointers(next)
+                    .as_mut()
+                    .set_prev(L::pointers(node).as_ref().get_prev());
+            } else {
+                // // This might be the last item in the list
+                // if self.tail != Some(node) {
+                //     return None;
+                // }
+
+                // self.tail = L::pointers(node).as_ref().get_prev();
+            }
 
-        if let Some(next) = L::pointers(node).as_ref().get_next() {
-            debug_assert_eq!(L::pointers(next).as_ref().get_prev(), Some(node));
-            L::pointers(next)
-                .as_mut()
-                .set_prev(L::pointers(node).as_ref().get_prev());
-        } else {
-            // // This might be the last item in the list
-            // if self.tail != Some(node) {
-            //     return None;
-            // }
+            L::pointers(node).as_mut().set_next(None);
+            L::pointers(node).as_mut().set_prev(None);
 
-            // self.tail = L::pointers(node).as_ref().get_prev();
+            Some(L::from_raw(node))
         }
-
-        L::pointers(node).as_mut().set_next(None);
-        L::pointers(node).as_mut().set_prev(None);
-
-        Some(L::from_raw(node))
     }
 
     // pub fn last(&self) -> Option<&L::Target> {
diff --git a/common/src/lock/cell_lock.rs b/common/src/lock/cell_lock.rs
index b10101f269..1edd622a20 100644
--- a/common/src/lock/cell_lock.rs
+++ b/common/src/lock/cell_lock.rs
@@ -140,12 +140,12 @@ unsafe impl RawRwLockUpgrade for RawCellRwLock {
 
     #[inline]
     unsafe fn unlock_upgradable(&self) {
-        self.unlock_shared()
+        unsafe { self.unlock_shared() }
     }
 
     #[inline]
     unsafe fn upgrade(&self) {
-        if !self.try_upgrade() {
+        if !unsafe { self.try_upgrade() } {
             deadlock("upgrade ", "RwLock")
         }
     }
diff --git a/common/src/lock/thread_mutex.rs b/common/src/lock/thread_mutex.rs
index ba36898780..35b0b9ac6d 100644
--- a/common/src/lock/thread_mutex.rs
+++ b/common/src/lock/thread_mutex.rs
@@ -65,7 +65,7 @@ impl<R: RawMutex, G: GetThreadId> RawThreadMutex<R, G> {
     /// This method may only be called if the mutex is held by the current thread.
     pub unsafe fn unlock(&self) {
         self.owner.store(0, Ordering::Relaxed);
-        self.mutex.unlock();
+        unsafe { self.mutex.unlock() };
     }
 }
 
diff --git a/common/src/macros.rs b/common/src/macros.rs
index 318ab06986..08d00e592d 100644
--- a/common/src/macros.rs
+++ b/common/src/macros.rs
@@ -41,7 +41,7 @@ pub mod __macro_private {
         libc::uintptr_t,
     );
     #[cfg(target_env = "msvc")]
-    extern "C" {
+    unsafe extern "C" {
         pub fn _set_thread_local_invalid_parameter_handler(
             pNew: InvalidParamHandler,
         ) -> InvalidParamHandler;
diff --git a/common/src/os.rs b/common/src/os.rs
index c16ec014c5..8a832270bc 100644
--- a/common/src/os.rs
+++ b/common/src/os.rs
@@ -23,7 +23,7 @@ pub fn last_os_error() -> io::Error {
     let err = io::Error::last_os_error();
     // FIXME: probably not ideal, we need a bigger dichotomy between GetLastError and errno
     if err.raw_os_error() == Some(0) {
-        extern "C" {
+        unsafe extern "C" {
             fn _get_errno(pValue: *mut i32) -> i32;
         }
         let mut errno = 0;
@@ -44,7 +44,7 @@ pub fn last_os_error() -> io::Error {
 pub fn last_posix_errno() -> i32 {
     let err = io::Error::last_os_error();
     if err.raw_os_error() == Some(0) {
-        extern "C" {
+        unsafe extern "C" {
             fn _get_errno(pValue: *mut i32) -> i32;
         }
         let mut errno = 0;
diff --git a/common/src/str.rs b/common/src/str.rs
index 3f9bf583b8..b4f7a1a636 100644
--- a/common/src/str.rs
+++ b/common/src/str.rs
@@ -241,11 +241,7 @@ pub mod levenshtein {
         if b.is_ascii_uppercase() {
             b += b'a' - b'A';
         }
-        if a == b {
-            CASE_COST
-        } else {
-            MOVE_COST
-        }
+        if a == b { CASE_COST } else { MOVE_COST }
     }
 
     pub fn levenshtein_distance(a: &str, b: &str, max_cost: usize) -> usize {
@@ -322,6 +318,37 @@ pub mod levenshtein {
     }
 }
 
+/// Replace all tabs in a string with spaces, using the given tab size.
+pub fn expandtabs(input: &str, tab_size: usize) -> String {
+    let tab_stop = tab_size;
+    let mut expanded_str = String::with_capacity(input.len());
+    let mut tab_size = tab_stop;
+    let mut col_count = 0usize;
+    for ch in input.chars() {
+        match ch {
+            '\t' => {
+                let num_spaces = tab_size - col_count;
+                col_count += num_spaces;
+                let expand = " ".repeat(num_spaces);
+                expanded_str.push_str(&expand);
+            }
+            '\r' | '\n' => {
+                expanded_str.push(ch);
+                col_count = 0;
+                tab_size = 0;
+            }
+            _ => {
+                expanded_str.push(ch);
+                col_count += 1;
+            }
+        }
+        if col_count >= tab_size {
+            tab_size += tab_stop;
+        }
+    }
+    expanded_str
+}
+
 /// Creates an [`AsciiStr`][ascii::AsciiStr] from a string literal, throwing a compile error if the
 /// literal isn't actually ascii.
 ///
diff --git a/compiler/codegen/Cargo.toml b/compiler/codegen/Cargo.toml
index 0fe950be71..0817a95894 100644
--- a/compiler/codegen/Cargo.toml
+++ b/compiler/codegen/Cargo.toml
@@ -11,6 +11,7 @@ license.workspace = true
 
 [dependencies]
 rustpython-ast = { workspace = true, features=["unparse", "constant-optimization"] }
+rustpython-common = { workspace = true }
 rustpython-parser-core = { workspace = true }
 rustpython-compiler-core = { workspace = true }
 
diff --git a/compiler/codegen/src/compile.rs b/compiler/codegen/src/compile.rs
index eeb4b7dec6..6b1d15c720 100644
--- a/compiler/codegen/src/compile.rs
+++ b/compiler/codegen/src/compile.rs
@@ -8,18 +8,21 @@
 #![deny(clippy::cast_possible_truncation)]
 
 use crate::{
+    IndexSet,
     error::{CodegenError, CodegenErrorType},
     ir,
     symboltable::{self, SymbolFlags, SymbolScope, SymbolTable},
-    IndexSet,
 };
 use itertools::Itertools;
 use num_complex::Complex64;
 use num_traits::ToPrimitive;
 use rustpython_ast::located::{self as located_ast, Located};
 use rustpython_compiler_core::{
-    bytecode::{self, Arg as OpArgMarker, CodeObject, ConstantData, Instruction, OpArg, OpArgType},
     Mode,
+    bytecode::{
+        self, Arg as OpArgMarker, CodeObject, ComparisonOperator, ConstantData, Instruction, OpArg,
+        OpArgType,
+    },
 };
 use rustpython_parser_core::source_code::{LineNumber, SourceLocation};
 use std::borrow::Cow;
@@ -211,6 +214,12 @@ macro_rules! emit {
     };
 }
 
+struct PatternContext {
+    current_block: usize,
+    blocks: Vec<ir::BlockIdx>,
+    allow_irrefutable: bool,
+}
+
 impl Compiler {
     fn new(opts: CompileOpts, source_path: String, code_name: String) -> Self {
         let module_code = ir::CodeInfo {
@@ -966,7 +975,7 @@ impl Compiler {
                 }
             }
             located_ast::Expr::BinOp(_) | located_ast::Expr::UnaryOp(_) => {
-                return Err(self.error(CodegenErrorType::Delete("expression")))
+                return Err(self.error(CodegenErrorType::Delete("expression")));
             }
             _ => return Err(self.error(CodegenErrorType::Delete(expression.python_name()))),
         }
@@ -1086,8 +1095,27 @@ impl Compiler {
                         self.store_name(name.as_ref())?;
                     }
                 }
-                located_ast::TypeParam::ParamSpec(_) => todo!(),
-                located_ast::TypeParam::TypeVarTuple(_) => todo!(),
+                located_ast::TypeParam::ParamSpec(located_ast::TypeParamParamSpec {
+                    name, ..
+                }) => {
+                    self.emit_load_const(ConstantData::Str {
+                        value: name.to_string(),
+                    });
+                    emit!(self, Instruction::ParamSpec);
+                    emit!(self, Instruction::Duplicate);
+                    self.store_name(name.as_ref())?;
+                }
+                located_ast::TypeParam::TypeVarTuple(located_ast::TypeParamTypeVarTuple {
+                    name,
+                    ..
+                }) => {
+                    self.emit_load_const(ConstantData::Str {
+                        value: name.to_string(),
+                    });
+                    emit!(self, Instruction::TypeVarTuple);
+                    emit!(self, Instruction::Duplicate);
+                    self.store_name(name.as_ref())?;
+                }
             };
         }
         emit!(
@@ -1185,7 +1213,7 @@ impl Compiler {
 
             if !finalbody.is_empty() {
                 emit!(self, Instruction::PopBlock); // pop excepthandler block
-                                                    // We enter the finally block, without exception.
+                // We enter the finally block, without exception.
                 emit!(self, Instruction::EnterFinally);
             }
 
@@ -1755,14 +1783,152 @@ impl Compiler {
         Ok(())
     }
 
+    fn compile_pattern_value(
+        &mut self,
+        value: &located_ast::PatternMatchValue,
+        _pattern_context: &mut PatternContext,
+    ) -> CompileResult<()> {
+        self.compile_expression(&value.value)?;
+        emit!(
+            self,
+            Instruction::CompareOperation {
+                op: ComparisonOperator::Equal
+            }
+        );
+        Ok(())
+    }
+
+    fn compile_pattern_as(
+        &mut self,
+        as_pattern: &located_ast::PatternMatchAs,
+        pattern_context: &mut PatternContext,
+    ) -> CompileResult<()> {
+        if as_pattern.pattern.is_none() && !pattern_context.allow_irrefutable {
+            // TODO: better error message
+            if let Some(_name) = as_pattern.name.as_ref() {
+                return Err(
+                    self.error_loc(CodegenErrorType::InvalidMatchCase, as_pattern.location())
+                );
+            }
+            return Err(self.error_loc(CodegenErrorType::InvalidMatchCase, as_pattern.location()));
+        }
+        // Need to make a copy for (possibly) storing later:
+        emit!(self, Instruction::Duplicate);
+        if let Some(pattern) = &as_pattern.pattern {
+            self.compile_pattern_inner(pattern, pattern_context)?;
+        }
+        if let Some(name) = as_pattern.name.as_ref() {
+            self.store_name(name.as_str())?;
+        } else {
+            emit!(self, Instruction::Pop);
+        }
+        Ok(())
+    }
+
+    fn compile_pattern_inner(
+        &mut self,
+        pattern_type: &located_ast::Pattern,
+        pattern_context: &mut PatternContext,
+    ) -> CompileResult<()> {
+        match &pattern_type {
+            located_ast::Pattern::MatchValue(value) => {
+                self.compile_pattern_value(value, pattern_context)
+            }
+            located_ast::Pattern::MatchAs(as_pattern) => {
+                self.compile_pattern_as(as_pattern, pattern_context)
+            }
+            _ => {
+                eprintln!("not implemented pattern type: {pattern_type:?}");
+                Err(self.error(CodegenErrorType::NotImplementedYet))
+            }
+        }
+    }
+
+    fn compile_pattern(
+        &mut self,
+        pattern_type: &located_ast::Pattern,
+        pattern_context: &mut PatternContext,
+    ) -> CompileResult<()> {
+        self.compile_pattern_inner(pattern_type, pattern_context)?;
+        emit!(
+            self,
+            Instruction::JumpIfFalse {
+                target: pattern_context.blocks[pattern_context.current_block + 1]
+            }
+        );
+        Ok(())
+    }
+
+    fn compile_match_inner(
+        &mut self,
+        subject: &located_ast::Expr,
+        cases: &[located_ast::MatchCase],
+        pattern_context: &mut PatternContext,
+    ) -> CompileResult<()> {
+        self.compile_expression(subject)?;
+        pattern_context.blocks = std::iter::repeat_with(|| self.new_block())
+            .take(cases.len() + 1)
+            .collect::<Vec<_>>();
+        let end_block = *pattern_context.blocks.last().unwrap();
+
+        let _match_case_type = cases.last().expect("cases is not empty");
+        // TODO: get proper check for default case
+        // let has_default = match_case_type.pattern.is_match_as() && 1 < cases.len();
+        let has_default = false;
+        for i in 0..cases.len() - (has_default as usize) {
+            self.switch_to_block(pattern_context.blocks[i]);
+            pattern_context.current_block = i;
+            pattern_context.allow_irrefutable = cases[i].guard.is_some() || i == cases.len() - 1;
+            let m = &cases[i];
+            // Only copy the subject if we're *not* on the last case:
+            if i != cases.len() - has_default as usize - 1 {
+                emit!(self, Instruction::Duplicate);
+            }
+            self.compile_pattern(&m.pattern, pattern_context)?;
+            self.compile_statements(&m.body)?;
+            emit!(self, Instruction::Jump { target: end_block });
+        }
+        // TODO: below code is not called and does not work
+        if has_default {
+            // A trailing "case _" is common, and lets us save a bit of redundant
+            // pushing and popping in the loop above:
+            let m = &cases.last().unwrap();
+            self.switch_to_block(*pattern_context.blocks.last().unwrap());
+            if cases.len() == 1 {
+                // No matches. Done with the subject:
+                emit!(self, Instruction::Pop);
+            } else {
+                // Show line coverage for default case (it doesn't create bytecode)
+                // emit!(self, Instruction::Nop);
+            }
+            self.compile_statements(&m.body)?;
+        }
+
+        self.switch_to_block(end_block);
+
+        let code = self.current_code_info();
+        pattern_context
+            .blocks
+            .iter()
+            .zip(pattern_context.blocks.iter().skip(1))
+            .for_each(|(a, b)| {
+                code.blocks[a.0 as usize].next = *b;
+            });
+        Ok(())
+    }
+
     fn compile_match(
         &mut self,
         subject: &located_ast::Expr,
         cases: &[located_ast::MatchCase],
     ) -> CompileResult<()> {
-        eprintln!("match subject: {subject:?}");
-        eprintln!("match cases: {cases:?}");
-        Err(self.error(CodegenErrorType::NotImplementedYet))
+        let mut pattern_context = PatternContext {
+            current_block: usize::MAX,
+            blocks: Vec::new(),
+            allow_irrefutable: false,
+        };
+        self.compile_match_inner(subject, cases, &mut pattern_context)?;
+        Ok(())
     }
 
     fn compile_chained_comparison(
@@ -2557,7 +2723,7 @@ impl Compiler {
 
     fn compile_keywords(&mut self, keywords: &[located_ast::Keyword]) -> CompileResult<()> {
         let mut size = 0;
-        let groupby = keywords.iter().group_by(|e| e.arg.is_none());
+        let groupby = keywords.iter().chunk_by(|e| e.arg.is_none());
         for (is_unpacking, sub_keywords) in &groupby {
             if is_unpacking {
                 for keyword in sub_keywords {
@@ -2720,7 +2886,7 @@ impl Compiler {
                         (false, element)
                     }
                 })
-                .group_by(|(starred, _)| *starred);
+                .chunk_by(|(starred, _)| *starred);
 
             for (starred, run) in &groups {
                 let mut run_size = 0;
@@ -2958,7 +3124,9 @@ impl Compiler {
                 | "with_statement" | "print_function" | "unicode_literals" | "generator_stop" => {}
                 "annotations" => self.future_annotations = true,
                 other => {
-                    return Err(self.error(CodegenErrorType::InvalidFutureFeature(other.to_owned())))
+                    return Err(
+                        self.error(CodegenErrorType::InvalidFutureFeature(other.to_owned()))
+                    );
                 }
             }
         }
@@ -3036,16 +3204,17 @@ impl Compiler {
     fn switch_to_block(&mut self, block: ir::BlockIdx) {
         let code = self.current_code_info();
         let prev = code.current_block;
+        assert_ne!(prev, block, "recursive switching {prev:?} -> {block:?}");
         assert_eq!(
             code.blocks[block].next,
             ir::BlockIdx::NULL,
-            "switching to completed block"
+            "switching {prev:?} -> {block:?} to completed block"
         );
         let prev_block = &mut code.blocks[prev.0 as usize];
         assert_eq!(
             prev_block.next.0,
             u32::MAX,
-            "switching from block that's already got a next"
+            "switching {prev:?} -> {block:?} from block that's already got a next"
         );
         prev_block.next = block;
         code.current_block = block;
@@ -3135,13 +3304,13 @@ impl Compiler {
                 elt, generators, ..
             }) => {
                 Self::contains_await(elt)
-                    || generators.iter().any(|gen| Self::contains_await(&gen.iter))
+                    || generators.iter().any(|jen| Self::contains_await(&jen.iter))
             }
             Expr::SetComp(located_ast::ExprSetComp {
                 elt, generators, ..
             }) => {
                 Self::contains_await(elt)
-                    || generators.iter().any(|gen| Self::contains_await(&gen.iter))
+                    || generators.iter().any(|jen| Self::contains_await(&jen.iter))
             }
             Expr::DictComp(located_ast::ExprDictComp {
                 key,
@@ -3151,13 +3320,13 @@ impl Compiler {
             }) => {
                 Self::contains_await(key)
                     || Self::contains_await(value)
-                    || generators.iter().any(|gen| Self::contains_await(&gen.iter))
+                    || generators.iter().any(|jen| Self::contains_await(&jen.iter))
             }
             Expr::GeneratorExp(located_ast::ExprGeneratorExp {
                 elt, generators, ..
             }) => {
                 Self::contains_await(elt)
-                    || generators.iter().any(|gen| Self::contains_await(&gen.iter))
+                    || generators.iter().any(|jen| Self::contains_await(&jen.iter))
             }
             Expr::Starred(expr) => Self::contains_await(&expr.value),
             Expr::IfExp(located_ast::ExprIfExp {
@@ -3201,17 +3370,51 @@ impl EmitArg<bytecode::Label> for ir::BlockIdx {
     }
 }
 
+/// Strips leading whitespace from a docstring.
+///
+/// The code has been ported from `_PyCompile_CleanDoc` in cpython.
+/// `inspect.cleandoc` is also a good reference, but has a few incompatibilities.
+fn clean_doc(doc: &str) -> String {
+    let doc = rustpython_common::str::expandtabs(doc, 8);
+    // First pass: find minimum indentation of any non-blank lines
+    // after first line.
+    let margin = doc
+        .lines()
+        // Find the non-blank lines
+        .filter(|line| !line.trim().is_empty())
+        // get the one with the least indentation
+        .map(|line| line.chars().take_while(|c| c == &' ').count())
+        .min();
+    if let Some(margin) = margin {
+        let mut cleaned = String::with_capacity(doc.len());
+        // copy first line without leading whitespace
+        if let Some(first_line) = doc.lines().next() {
+            cleaned.push_str(first_line.trim_start());
+        }
+        // copy subsequent lines without margin.
+        for line in doc.split('\n').skip(1) {
+            cleaned.push('\n');
+            let cleaned_line = line.chars().skip(margin).collect::<String>();
+            cleaned.push_str(&cleaned_line);
+        }
+
+        cleaned
+    } else {
+        doc.to_owned()
+    }
+}
+
 fn split_doc<'a>(
     body: &'a [located_ast::Stmt],
     opts: &CompileOpts,
 ) -> (Option<String>, &'a [located_ast::Stmt]) {
     if let Some((located_ast::Stmt::Expr(expr), body_rest)) = body.split_first() {
         if let Some(doc) = try_get_constant_string(std::slice::from_ref(&expr.value)) {
-            if opts.optimize < 2 {
-                return (Some(doc), body_rest);
+            return if opts.optimize < 2 {
+                (Some(clean_doc(&doc)), body_rest)
             } else {
-                return (None, body_rest);
-            }
+                (None, body_rest)
+            };
         }
     }
     (None, body)
@@ -3276,8 +3479,8 @@ impl ToU32 for usize {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use rustpython_parser::ast::Suite;
     use rustpython_parser::Parse;
+    use rustpython_parser::ast::Suite;
     use rustpython_parser_core::source_code::LinearLocator;
 
     fn compile_exec(source: &str) -> CodeObject {
diff --git a/compiler/codegen/src/error.rs b/compiler/codegen/src/error.rs
index 017f735105..27333992df 100644
--- a/compiler/codegen/src/error.rs
+++ b/compiler/codegen/src/error.rs
@@ -30,6 +30,8 @@ pub enum CodegenErrorType {
     TooManyStarUnpack,
     EmptyWithItems,
     EmptyWithBody,
+    DuplicateStore(String),
+    InvalidMatchCase,
     NotImplementedYet, // RustPython marker for unimplemented features
 }
 
@@ -75,6 +77,12 @@ impl fmt::Display for CodegenErrorType {
             EmptyWithBody => {
                 write!(f, "empty body on With")
             }
+            DuplicateStore(s) => {
+                write!(f, "duplicate store {s}")
+            }
+            InvalidMatchCase => {
+                write!(f, "invalid match case")
+            }
             NotImplementedYet => {
                 write!(f, "RustPython does not implement this feature yet")
             }
diff --git a/compiler/codegen/src/ir.rs b/compiler/codegen/src/ir.rs
index 9f1a86e51d..08e68d283a 100644
--- a/compiler/codegen/src/ir.rs
+++ b/compiler/codegen/src/ir.rs
@@ -199,11 +199,7 @@ impl CodeInfo {
             })
             .collect::<Box<[_]>>();
 
-        if found_cellarg {
-            Some(cell2arg)
-        } else {
-            None
-        }
+        if found_cellarg { Some(cell2arg) } else { None }
     }
 
     fn dce(&mut self) {
diff --git a/compiler/codegen/src/symboltable.rs b/compiler/codegen/src/symboltable.rs
index 8522c82037..7db5c4edbe 100644
--- a/compiler/codegen/src/symboltable.rs
+++ b/compiler/codegen/src/symboltable.rs
@@ -8,8 +8,8 @@ Inspirational file: https://github.com/python/cpython/blob/main/Python/symtable.
 */
 
 use crate::{
-    error::{CodegenError, CodegenErrorType},
     IndexMap,
+    error::{CodegenError, CodegenErrorType},
 };
 use bitflags::bitflags;
 use rustpython_ast::{self as ast, located::Located};
@@ -505,7 +505,10 @@ impl SymbolTableAnalyzer {
                         // check if assignee is an iterator in top scope
                         if parent_symbol.flags.contains(SymbolFlags::ITER) {
                             return Err(SymbolTableError {
-                                error: format!("assignment expression cannot rebind comprehension iteration variable {}", symbol.name),
+                                error: format!(
+                                    "assignment expression cannot rebind comprehension iteration variable {}",
+                                    symbol.name
+                                ),
                                 location: None,
                             });
                         }
@@ -886,11 +889,13 @@ impl SymbolTableBuilder {
                 self.scan_statements(orelse)?;
                 self.scan_statements(finalbody)?;
             }
-            Stmt::Match(StmtMatch { subject, .. }) => {
-                return Err(SymbolTableError {
-                    error: "match expression is not implemented yet".to_owned(),
-                    location: Some(subject.location()),
-                });
+            Stmt::Match(StmtMatch { subject, cases, .. }) => {
+                self.scan_expression(subject, ExpressionContext::Load)?;
+                for case in cases {
+                    // TODO: below
+                    // self.scan_pattern(&case.pattern, ExpressionContext::Load)?;
+                    self.scan_statements(&case.body)?;
+                }
             }
             Stmt::Raise(StmtRaise { exc, cause, .. }) => {
                 if let Some(expression) = exc {
@@ -1255,8 +1260,18 @@ impl SymbolTableBuilder {
                         self.scan_expression(binding, ExpressionContext::Load)?;
                     }
                 }
-                ast::located::TypeParam::ParamSpec(_) => todo!(),
-                ast::located::TypeParam::TypeVarTuple(_) => todo!(),
+                ast::located::TypeParam::ParamSpec(ast::TypeParamParamSpec {
+                    name,
+                    range: param_spec_range,
+                }) => {
+                    self.register_name(name, SymbolUsage::Assigned, param_spec_range.start)?;
+                }
+                ast::located::TypeParam::TypeVarTuple(ast::TypeParamTypeVarTuple {
+                    name,
+                    range: type_var_tuple_range,
+                }) => {
+                    self.register_name(name, SymbolUsage::Assigned, type_var_tuple_range.start)?;
+                }
             }
         }
         Ok(())
@@ -1396,7 +1411,7 @@ impl SymbolTableBuilder {
                     return Err(SymbolTableError {
                         error: format!("cannot define nonlocal '{name}' at top level."),
                         location,
-                    })
+                    });
                 }
                 _ => {
                     // Ok!
diff --git a/compiler/core/Cargo.toml b/compiler/core/Cargo.toml
index 3d05fc2734..619ffcf61e 100644
--- a/compiler/core/Cargo.toml
+++ b/compiler/core/Cargo.toml
@@ -15,7 +15,7 @@ bitflags = { workspace = true }
 itertools = { workspace = true }
 malachite-bigint = { workspace = true }
 num-complex = { workspace = true }
-serde = { version = "1.0.133", optional = true, default-features = false, features = ["derive"] }
+serde = { version = "1.0.217", optional = true, default-features = false, features = ["derive"] }
 
 lz4_flex = "0.11"
 
diff --git a/compiler/core/src/bytecode.rs b/compiler/core/src/bytecode.rs
index c8dbc63744..11e49a47db 100644
--- a/compiler/core/src/bytecode.rs
+++ b/compiler/core/src/bytecode.rs
@@ -197,7 +197,7 @@ impl OpArgState {
     }
     #[inline(always)]
     pub fn extend(&mut self, arg: OpArgByte) -> OpArg {
-        self.state = self.state << 8 | u32::from(arg.0);
+        self.state = (self.state << 8) | u32::from(arg.0);
         OpArg(self.state)
     }
     #[inline(always)]
@@ -293,10 +293,8 @@ impl<T: OpArgType> Arg<T> {
     /// # Safety
     /// T::from_op_arg(self) must succeed
     pub unsafe fn get_unchecked(self, arg: OpArg) -> T {
-        match T::from_op_arg(arg.0) {
-            Some(t) => t,
-            None => std::hint::unreachable_unchecked(),
-        }
+        // SAFETY: requirements forwarded from caller
+        unsafe { T::from_op_arg(arg.0).unwrap_unchecked() }
     }
 }
 
@@ -595,10 +593,12 @@ pub enum Instruction {
     TypeVarWithBound,
     TypeVarWithConstraint,
     TypeAlias,
+    TypeVarTuple,
+    ParamSpec,
     // If you add a new instruction here, be sure to keep LAST_INSTRUCTION updated
 }
 // This must be kept up to date to avoid marshaling errors
-const LAST_INSTRUCTION: Instruction = Instruction::TypeAlias;
+const LAST_INSTRUCTION: Instruction = Instruction::ParamSpec;
 const _: () = assert!(mem::size_of::<Instruction>() == 1);
 
 impl From<Instruction> for u8 {
@@ -1291,6 +1291,8 @@ impl Instruction {
             TypeVarWithBound => -1,
             TypeVarWithConstraint => -1,
             TypeAlias => -2,
+            ParamSpec => 0,
+            TypeVarTuple => 0,
         }
     }
 
@@ -1460,6 +1462,8 @@ impl Instruction {
             TypeVarWithBound => w!(TypeVarWithBound),
             TypeVarWithConstraint => w!(TypeVarWithConstraint),
             TypeAlias => w!(TypeAlias),
+            ParamSpec => w!(ParamSpec),
+            TypeVarTuple => w!(TypeVarTuple),
         }
     }
 }
diff --git a/compiler/src/lib.rs b/compiler/src/lib.rs
index c281058555..7d226cd1ce 100644
--- a/compiler/src/lib.rs
+++ b/compiler/src/lib.rs
@@ -1,9 +1,9 @@
 use rustpython_codegen::{compile, symboltable};
-use rustpython_parser::ast::{self as ast, fold::Fold, ConstantOptimizer};
+use rustpython_parser::ast::{self as ast, ConstantOptimizer, fold::Fold};
 
 pub use rustpython_codegen::compile::CompileOpts;
-pub use rustpython_compiler_core::{bytecode::CodeObject, Mode};
-pub use rustpython_parser::{source_code::LinearLocator, Parse};
+pub use rustpython_compiler_core::{Mode, bytecode::CodeObject};
+pub use rustpython_parser::{Parse, source_code::LinearLocator};
 
 // these modules are out of repository. re-exporting them here for convenience.
 pub use rustpython_codegen as codegen;
diff --git a/derive-impl/Cargo.toml b/derive-impl/Cargo.toml
index a843f5d3c5..debe58106b 100644
--- a/derive-impl/Cargo.toml
+++ b/derive-impl/Cargo.toml
@@ -18,10 +18,10 @@ once_cell = { workspace = true }
 syn = { workspace = true, features = ["full", "extra-traits"] }
 
 maplit = "1.0.2"
-proc-macro2 = "1.0.79"
-quote = "1.0.18"
-syn-ext = { version = "0.4.0", features = ["full"] }
-textwrap = { version = "0.15.0", default-features = false }
+proc-macro2 = "1.0.93"
+quote = "1.0.38"
+syn-ext = { version = "0.5.0", features = ["full"] }
+textwrap = { version = "0.16.1", default-features = false }
 
 [lints]
 workspace = true
\ No newline at end of file
diff --git a/derive-impl/src/compile_bytecode.rs b/derive-impl/src/compile_bytecode.rs
index 6b5baef98c..2a57134197 100644
--- a/derive-impl/src/compile_bytecode.rs
+++ b/derive-impl/src/compile_bytecode.rs
@@ -13,22 +13,20 @@
 //! )
 //! ```
 
-use crate::{extract_spans, Diagnostic};
+use crate::Diagnostic;
 use once_cell::sync::Lazy;
 use proc_macro2::{Span, TokenStream};
 use quote::quote;
-use rustpython_compiler_core::{bytecode::CodeObject, frozen, Mode};
+use rustpython_compiler_core::{Mode, bytecode::CodeObject, frozen};
 use std::{
     collections::HashMap,
     env, fs,
     path::{Path, PathBuf},
 };
 use syn::{
-    self,
-    parse::{Parse, ParseStream, Result as ParseResult},
-    parse2,
+    self, LitByteStr, LitStr, Macro,
+    parse::{ParseStream, Parser, Result as ParseResult},
     spanned::Spanned,
-    Lit, LitByteStr, LitStr, Macro, Meta, MetaNameValue, Token,
 };
 
 static CARGO_MANIFEST_DIR: Lazy<PathBuf> = Lazy::new(|| {
@@ -119,11 +117,13 @@ impl CompilationSource {
                 })?;
                 self.compile_string(&source, mode, module_name, compiler, || rel_path.display())
             }
-            CompilationSourceKind::SourceCode(code) => {
-                self.compile_string(&textwrap::dedent(code), mode, module_name, compiler, || {
-                    "string literal"
-                })
-            }
+            CompilationSourceKind::SourceCode(code) => self.compile_string(
+                &textwrap::dedent(code),
+                mode,
+                module_name,
+                compiler,
+                || "string literal",
+            ),
             CompilationSourceKind::Dir(_) => {
                 unreachable!("Can't use compile_single with directory source")
             }
@@ -233,23 +233,17 @@ impl CompilationSource {
     }
 }
 
-/// This is essentially just a comma-separated list of Meta nodes, aka the inside of a MetaList.
-struct PyCompileInput {
-    span: Span,
-    metas: Vec<Meta>,
-}
-
-impl PyCompileInput {
-    fn parse(&self, allow_dir: bool) -> Result<PyCompileArgs, Diagnostic> {
+impl PyCompileArgs {
+    fn parse(input: TokenStream, allow_dir: bool) -> Result<PyCompileArgs, Diagnostic> {
         let mut module_name = None;
         let mut mode = None;
         let mut source: Option<CompilationSource> = None;
         let mut crate_name = None;
 
-        fn assert_source_empty(source: &Option<CompilationSource>) -> Result<(), Diagnostic> {
+        fn assert_source_empty(source: &Option<CompilationSource>) -> Result<(), syn::Error> {
             if let Some(source) = source {
-                Err(Diagnostic::spans_error(
-                    source.span,
+                Err(syn::Error::new(
+                    source.span.0,
                     "Cannot have more than one source",
                 ))
             } else {
@@ -257,59 +251,58 @@ impl PyCompileInput {
             }
         }
 
-        for meta in &self.metas {
-            if let Meta::NameValue(name_value) = meta {
-                let ident = match name_value.path.get_ident() {
-                    Some(ident) => ident,
-                    None => continue,
-                };
-                let check_str = || match &name_value.lit {
-                    Lit::Str(s) => Ok(s),
-                    _ => Err(err_span!(name_value.lit, "{ident} must be a string")),
-                };
-                if ident == "mode" {
-                    let s = check_str()?;
-                    match s.value().parse() {
-                        Ok(mode_val) => mode = Some(mode_val),
-                        Err(e) => bail_span!(s, "{}", e),
-                    }
-                } else if ident == "module_name" {
-                    module_name = Some(check_str()?.value())
-                } else if ident == "source" {
-                    assert_source_empty(&source)?;
-                    let code = check_str()?.value();
-                    source = Some(CompilationSource {
-                        kind: CompilationSourceKind::SourceCode(code),
-                        span: extract_spans(&name_value).unwrap(),
-                    });
-                } else if ident == "file" {
-                    assert_source_empty(&source)?;
-                    let path = check_str()?.value().into();
-                    source = Some(CompilationSource {
-                        kind: CompilationSourceKind::File(path),
-                        span: extract_spans(&name_value).unwrap(),
-                    });
-                } else if ident == "dir" {
-                    if !allow_dir {
-                        bail_span!(ident, "py_compile doesn't accept dir")
-                    }
-
-                    assert_source_empty(&source)?;
-                    let path = check_str()?.value().into();
-                    source = Some(CompilationSource {
-                        kind: CompilationSourceKind::Dir(path),
-                        span: extract_spans(&name_value).unwrap(),
-                    });
-                } else if ident == "crate_name" {
-                    let name = check_str()?.parse()?;
-                    crate_name = Some(name);
+        syn::meta::parser(|meta| {
+            let ident = meta
+                .path
+                .get_ident()
+                .ok_or_else(|| meta.error("unknown arg"))?;
+            let check_str = || meta.value()?.call(parse_str);
+            if ident == "mode" {
+                let s = check_str()?;
+                match s.value().parse() {
+                    Ok(mode_val) => mode = Some(mode_val),
+                    Err(e) => bail_span!(s, "{}", e),
                 }
+            } else if ident == "module_name" {
+                module_name = Some(check_str()?.value())
+            } else if ident == "source" {
+                assert_source_empty(&source)?;
+                let code = check_str()?.value();
+                source = Some(CompilationSource {
+                    kind: CompilationSourceKind::SourceCode(code),
+                    span: (ident.span(), meta.input.cursor().span()),
+                });
+            } else if ident == "file" {
+                assert_source_empty(&source)?;
+                let path = check_str()?.value().into();
+                source = Some(CompilationSource {
+                    kind: CompilationSourceKind::File(path),
+                    span: (ident.span(), meta.input.cursor().span()),
+                });
+            } else if ident == "dir" {
+                if !allow_dir {
+                    bail_span!(ident, "py_compile doesn't accept dir")
+                }
+
+                assert_source_empty(&source)?;
+                let path = check_str()?.value().into();
+                source = Some(CompilationSource {
+                    kind: CompilationSourceKind::Dir(path),
+                    span: (ident.span(), meta.input.cursor().span()),
+                });
+            } else if ident == "crate_name" {
+                let name = check_str()?.parse()?;
+                crate_name = Some(name);
+            } else {
+                return Err(meta.error("unknown attr"));
             }
-        }
+            Ok(())
+        })
+        .parse2(input)?;
 
         let source = source.ok_or_else(|| {
             syn::Error::new(
-                self.span,
+                Span::call_site(),
                 "Must have either file or source in py_compile!()/py_freeze!()",
             )
         })?;
@@ -323,38 +316,17 @@ impl PyCompileInput {
     }
 }
 
-fn parse_meta(input: ParseStream) -> ParseResult<Meta> {
-    let path = input.call(syn::Path::parse_mod_style)?;
-    let eq_token: Token![=] = input.parse()?;
+fn parse_str(input: ParseStream) -> ParseResult<LitStr> {
     let span = input.span();
     if input.peek(LitStr) {
-        Ok(Meta::NameValue(MetaNameValue {
-            path,
-            eq_token,
-            lit: Lit::Str(input.parse()?),
-        }))
+        input.parse()
     } else if let Ok(mac) = input.parse::<Macro>() {
-        Ok(Meta::NameValue(MetaNameValue {
-            path,
-            eq_token,
-            lit: Lit::Str(LitStr::new(&mac.tokens.to_string(), mac.span())),
-        }))
+        Ok(LitStr::new(&mac.tokens.to_string(), mac.span()))
     } else {
         Err(syn::Error::new(span, "Expected string or stringify macro"))
     }
 }
 
-impl Parse for PyCompileInput {
-    fn parse(input: ParseStream) -> ParseResult<Self> {
-        let span = input.cursor().span();
-        let metas = input
-            .parse_terminated::<Meta, Token![,]>(parse_meta)?
-            .into_iter()
-            .collect();
-        Ok(PyCompileInput { span, metas })
-    }
-}
-
 struct PyCompileArgs {
     source: CompilationSource,
     mode: Mode,
@@ -366,8 +338,7 @@ pub fn impl_py_compile(
     input: TokenStream,
     compiler: &dyn Compiler,
 ) -> Result<TokenStream, Diagnostic> {
-    let input: PyCompileInput = parse2(input)?;
-    let args = input.parse(false)?;
+    let args = PyCompileArgs::parse(input, false)?;
 
     let crate_name = args.crate_name;
     let code = args
@@ -388,8 +359,7 @@ pub fn impl_py_freeze(
     input: TokenStream,
     compiler: &dyn Compiler,
 ) -> Result<TokenStream, Diagnostic> {
-    let input: PyCompileInput = parse2(input)?;
-    let args = input.parse(true)?;
+    let args = PyCompileArgs::parse(input, true)?;
 
     let crate_name = args.crate_name;
     let code_map = args.source.compile(args.mode, args.module_name, compiler)?;
diff --git a/derive-impl/src/from_args.rs b/derive-impl/src/from_args.rs
index 7b5b684213..2273046ed4 100644
--- a/derive-impl/src/from_args.rs
+++ b/derive-impl/src/from_args.rs
@@ -1,9 +1,8 @@
 use proc_macro2::TokenStream;
-use quote::{quote, ToTokens};
+use quote::{ToTokens, quote};
 use syn::ext::IdentExt;
-use syn::{
-    parse_quote, Attribute, Data, DeriveInput, Expr, Field, Ident, Lit, Meta, NestedMeta, Result,
-};
+use syn::meta::ParseNestedMeta;
+use syn::{Attribute, Data, DeriveInput, Expr, Field, Ident, Result, Token, parse_quote};
 
 /// The kind of the python parameter, this corresponds to the value of Parameter.kind
 /// (https://docs.python.org/3/library/inspect.html#inspect.Parameter.kind)
@@ -36,84 +35,61 @@ type DefaultValue = Option<Expr>;
 
 impl ArgAttribute {
     fn from_attribute(attr: &Attribute) -> Option<Result<ArgAttribute>> {
-        if !attr.path.is_ident("pyarg") {
+        if !attr.path().is_ident("pyarg") {
             return None;
         }
         let inner = move || {
-            let Meta::List(list) = attr.parse_meta()? else {
-                bail_span!(attr, "pyarg must be a list, like #[pyarg(...)]")
-            };
-            let mut iter = list.nested.iter();
-            let first_arg = iter.next().ok_or_else(|| {
-                err_span!(list, "There must be at least one argument to #[pyarg()]")
+            let mut arg_attr = None;
+            attr.parse_nested_meta(|meta| {
+                let Some(arg_attr) = &mut arg_attr else {
+                    let kind = meta
+                        .path
+                        .get_ident()
+                        .and_then(ParameterKind::from_ident)
+                        .ok_or_else(|| {
+                            meta.error(
+                                "The first argument to #[pyarg()] must be the parameter type, \
+                                 either 'positional', 'any', 'named', or 'flatten'.",
+                            )
+                        })?;
+                    arg_attr = Some(ArgAttribute {
+                        name: None,
+                        kind,
+                        default: None,
+                    });
+                    return Ok(());
+                };
+                arg_attr.parse_argument(meta)
             })?;
-            let kind = match first_arg {
-                NestedMeta::Meta(Meta::Path(path)) => {
-                    path.get_ident().and_then(ParameterKind::from_ident)
-                }
-                _ => None,
-            };
-            let kind = kind.ok_or_else(|| {
-                err_span!(
-                    first_arg,
-                    "The first argument to #[pyarg()] must be the parameter type, either \
-                         'positional', 'any', 'named', or 'flatten'."
-                )
-            })?;
-
-            let mut attribute = ArgAttribute {
-                name: None,
-                kind,
-                default: None,
-            };
-
-            for arg in iter {
-                attribute.parse_argument(arg)?;
-            }
-
-            Ok(attribute)
+            arg_attr
+                .ok_or_else(|| err_span!(attr, "There must be at least one argument to #[pyarg()]"))
         };
         Some(inner())
     }
 
-    fn parse_argument(&mut self, arg: &NestedMeta) -> Result<()> {
+    fn parse_argument(&mut self, meta: ParseNestedMeta<'_>) -> Result<()> {
         if let ParameterKind::Flatten = self.kind {
-            bail_span!(arg, "can't put additional arguments on a flatten arg")
+            return Err(meta.error("can't put additional arguments on a flatten arg"));
         }
-        match arg {
-            NestedMeta::Meta(Meta::Path(path)) => {
-                if path.is_ident("default") || path.is_ident("optional") {
-                    if self.default.is_none() {
-                        self.default = Some(None);
-                    }
-                } else {
-                    bail_span!(path, "Unrecognized pyarg attribute");
-                }
+        if meta.path.is_ident("default") && meta.input.peek(Token![=]) {
+            if matches!(self.default, Some(Some(_))) {
+                return Err(meta.error("Default already set"));
             }
-            NestedMeta::Meta(Meta::NameValue(name_value)) => {
-                if name_value.path.is_ident("default") {
-                    if matches!(self.default, Some(Some(_))) {
-                        bail_span!(name_value, "Default already set");
-                    }
-
-                    match name_value.lit {
-                        Lit::Str(ref val) => self.default = Some(Some(val.parse()?)),
-                        _ => bail_span!(name_value, "Expected string value for default argument"),
-                    }
-                } else if name_value.path.is_ident("name") {
-                    if self.name.is_some() {
-                        bail_span!(name_value, "already have a name")
-                    }
-
-                    match &name_value.lit {
-                        Lit::Str(val) => self.name = Some(val.value()),
-                        _ => bail_span!(name_value, "Expected string value for name argument"),
-                    }
-                } else {
-                    bail_span!(name_value, "Unrecognized pyarg attribute");
-                }
+            let val = meta.value()?;
+            let val = val.parse::<syn::LitStr>()?;
+            self.default = Some(Some(val.parse()?))
+        } else if meta.path.is_ident("default") || meta.path.is_ident("optional") {
+            if self.default.is_none() {
+                self.default = Some(None);
+            }
+        } else if meta.path.is_ident("name") {
+            if self.name.is_some() {
+                return Err(meta.error("already have a name"));
             }
-            _ => bail_span!(arg, "Unrecognized pyarg attribute"),
+            let val = meta.value()?.parse::<syn::LitStr>()?;
+            self.name = Some(val.value())
+        } else {
+            return Err(meta.error("Unrecognized pyarg attribute"));
         }
 
         Ok(())
diff --git a/derive-impl/src/lib.rs b/derive-impl/src/lib.rs
index 35292e7de0..a1f97c96b0 100644
--- a/derive-impl/src/lib.rs
+++ b/derive-impl/src/lib.rs
@@ -20,11 +20,12 @@ mod pypayload;
 mod pystructseq;
 mod pytraverse;
 
-use error::{extract_spans, Diagnostic};
+use error::Diagnostic;
 use proc_macro2::TokenStream;
 use quote::ToTokens;
 use rustpython_doc as doc;
-use syn::{AttributeArgs, DeriveInput, Item};
+use syn::{DeriveInput, Item};
+use syn_ext::types::PunctuatedNestedMeta;
 
 pub use compile_bytecode::Compiler;
 
@@ -38,7 +39,7 @@ pub fn derive_from_args(input: DeriveInput) -> TokenStream {
     result_to_tokens(from_args::impl_from_args(input))
 }
 
-pub fn pyclass(attr: AttributeArgs, item: Item) -> TokenStream {
+pub fn pyclass(attr: PunctuatedNestedMeta, item: Item) -> TokenStream {
     if matches!(item, syn::Item::Impl(_) | syn::Item::Trait(_)) {
         result_to_tokens(pyclass::impl_pyclass_impl(attr, item))
     } else {
@@ -46,7 +47,7 @@ pub fn pyclass(attr: AttributeArgs, item: Item) -> TokenStream {
     }
 }
 
-pub fn pyexception(attr: AttributeArgs, item: Item) -> TokenStream {
+pub fn pyexception(attr: PunctuatedNestedMeta, item: Item) -> TokenStream {
     if matches!(item, syn::Item::Impl(_)) {
         result_to_tokens(pyclass::impl_pyexception_impl(attr, item))
     } else {
@@ -54,7 +55,7 @@ pub fn pyexception(attr: AttributeArgs, item: Item) -> TokenStream {
     }
 }
 
-pub fn pymodule(attr: AttributeArgs, item: Item) -> TokenStream {
+pub fn pymodule(attr: PunctuatedNestedMeta, item: Item) -> TokenStream {
     result_to_tokens(pymodule::impl_pymodule(attr, item))
 }
 
diff --git a/derive-impl/src/pyclass.rs b/derive-impl/src/pyclass.rs
index dedb3eb77a..077bd36bb8 100644
--- a/derive-impl/src/pyclass.rs
+++ b/derive-impl/src/pyclass.rs
@@ -1,17 +1,16 @@
 use super::Diagnostic;
 use crate::util::{
-    format_doc, pyclass_ident_and_attrs, pyexception_ident_and_attrs, text_signature,
-    ClassItemMeta, ContentItem, ContentItemInner, ErrorVec, ExceptionItemMeta, ItemMeta,
-    ItemMetaInner, ItemNursery, SimpleItemMeta, ALL_ALLOWED_NAMES,
+    ALL_ALLOWED_NAMES, ClassItemMeta, ContentItem, ContentItemInner, ErrorVec, ExceptionItemMeta,
+    ItemMeta, ItemMetaInner, ItemNursery, SimpleItemMeta, format_doc, pyclass_ident_and_attrs,
+    pyexception_ident_and_attrs, text_signature,
 };
 use proc_macro2::{Delimiter, Group, Span, TokenStream, TokenTree};
-use quote::{quote, quote_spanned, ToTokens};
+use quote::{ToTokens, quote, quote_spanned};
 use std::collections::{HashMap, HashSet};
 use std::str::FromStr;
-use syn::{
-    parse_quote, spanned::Spanned, Attribute, AttributeArgs, Ident, Item, Meta, NestedMeta, Result,
-};
+use syn::{Attribute, Ident, Item, Result, parse_quote, spanned::Spanned};
 use syn_ext::ext::*;
+use syn_ext::types::*;
 
 #[derive(Copy, Clone, Debug)]
 enum AttrName {
@@ -98,7 +97,7 @@ fn extract_items_into_context<'a, Item>(
     context.errors.ok_or_push(context.member_items.validate());
 }
 
-pub(crate) fn impl_pyclass_impl(attr: AttributeArgs, item: Item) -> Result<TokenStream> {
+pub(crate) fn impl_pyclass_impl(attr: PunctuatedNestedMeta, item: Item) -> Result<TokenStream> {
     let mut context = ImplContext::default();
     let mut tokens = match item {
         Item::Impl(mut imp) => {
@@ -127,7 +126,7 @@ pub(crate) fn impl_pyclass_impl(attr: AttributeArgs, item: Item) -> Result<Token
                                         return Err(syn::Error::new_spanned(
                                             segment,
                                             "Py{Ref}<T> is expected but Py{Ref}<?> is found",
-                                        ))
+                                        ));
                                     }
                                 }
                             }
@@ -135,7 +134,7 @@ pub(crate) fn impl_pyclass_impl(attr: AttributeArgs, item: Item) -> Result<Token
                                 return Err(syn::Error::new_spanned(
                                     segment,
                                     "Py{Ref}<T> is expected but Py{Ref}? is found",
-                                ))
+                                ));
                             }
                         }
                     } else {
@@ -153,7 +152,7 @@ pub(crate) fn impl_pyclass_impl(attr: AttributeArgs, item: Item) -> Result<Token
                     return Err(syn::Error::new_spanned(
                         imp.self_ty,
                         "PyImpl can only be implemented for Py{Ref}<T> or T",
-                    ))
+                    ));
                 }
             };
 
@@ -235,9 +234,7 @@ pub(crate) fn impl_pyclass_impl(attr: AttributeArgs, item: Item) -> Result<Token
             let mut has_extend_slots = false;
             for item in &trai.items {
                 let has = match item {
-                    syn::TraitItem::Method(method) => {
-                        &method.sig.ident.to_string() == "extend_slots"
-                    }
+                    syn::TraitItem::Fn(item) => item.sig.ident == "extend_slots",
                     _ => false,
                 };
                 if has {
@@ -344,7 +341,7 @@ fn generate_class_def(
     };
     let basicsize = quote!(std::mem::size_of::<#ident>());
     let is_pystruct = attrs.iter().any(|attr| {
-        attr.path.is_ident("derive")
+        attr.path().is_ident("derive")
             && if let Ok(Meta::List(l)) = attr.parse_meta() {
                 l.nested
                     .into_iter()
@@ -418,7 +415,7 @@ fn generate_class_def(
     Ok(tokens)
 }
 
-pub(crate) fn impl_pyclass(attr: AttributeArgs, item: Item) -> Result<TokenStream> {
+pub(crate) fn impl_pyclass(attr: PunctuatedNestedMeta, item: Item) -> Result<TokenStream> {
     if matches!(item, syn::Item::Use(_)) {
         return Ok(quote!(#item));
     }
@@ -534,7 +531,7 @@ pub(crate) fn impl_pyclass(attr: AttributeArgs, item: Item) -> Result<TokenStrea
 /// But, inside `macro_rules` we don't have an opportunity
 /// to add non-literal attributes to `pyclass`.
 /// That's why we have to use this proxy.
-pub(crate) fn impl_pyexception(attr: AttributeArgs, item: Item) -> Result<TokenStream> {
+pub(crate) fn impl_pyexception(attr: PunctuatedNestedMeta, item: Item) -> Result<TokenStream> {
     let (ident, _attrs) = pyexception_ident_and_attrs(&item)?;
     let fake_ident = Ident::new("pyclass", item.span());
     let class_meta = ExceptionItemMeta::from_nested(ident.clone(), fake_ident, attr.into_iter())?;
@@ -573,7 +570,7 @@ pub(crate) fn impl_pyexception(attr: AttributeArgs, item: Item) -> Result<TokenS
     Ok(ret)
 }
 
-pub(crate) fn impl_pyexception_impl(attr: AttributeArgs, item: Item) -> Result<TokenStream> {
+pub(crate) fn impl_pyexception_impl(attr: PunctuatedNestedMeta, item: Item) -> Result<TokenStream> {
     let Item::Impl(imp) = item else {
         return Ok(item.into_token_stream());
     };
@@ -1229,15 +1226,18 @@ impl MethodItemMeta {
         let inner = self.inner();
         let name = inner._optional_str("name")?;
         let magic = inner._bool("magic")?;
+        if magic && name.is_some() {
+            bail_span!(
+                &inner.meta_ident,
+                "A #[{}] method cannot be magic and have a specified name, choose one.",
+                inner.meta_name()
+            );
+        }
         Ok(if let Some(name) = name {
             name
         } else {
             let name = inner.item_name();
-            if magic {
-                format!("__{name}__")
-            } else {
-                name
-            }
+            if magic { format!("__{name}__") } else { name }
         })
     }
 }
@@ -1304,11 +1304,7 @@ impl GetSetItemMeta {
                 GetSetItemKind::Set => extract_prefix_name("set_", "setter")?,
                 GetSetItemKind::Delete => extract_prefix_name("del_", "deleter")?,
             };
-            if magic {
-                format!("__{name}__")
-            } else {
-                name
-            }
+            if magic { format!("__{name}__") } else { name }
         };
         Ok((py_name, kind))
     }
@@ -1447,7 +1443,7 @@ struct ExtractedImplAttrs {
     with_slots: TokenStream,
 }
 
-fn extract_impl_attrs(attr: AttributeArgs, item: &Ident) -> Result<ExtractedImplAttrs> {
+fn extract_impl_attrs(attr: PunctuatedNestedMeta, item: &Ident) -> Result<ExtractedImplAttrs> {
     let mut withs = Vec::new();
     let mut with_method_defs = Vec::new();
     let mut with_slots = Vec::new();
@@ -1467,7 +1463,7 @@ fn extract_impl_attrs(attr: AttributeArgs, item: &Ident) -> Result<ExtractedImpl
     let mut has_constructor = false;
     for attr in attr {
         match attr {
-            NestedMeta::Meta(Meta::List(syn::MetaList { path, nested, .. })) => {
+            NestedMeta::Meta(Meta::List(MetaList { path, nested, .. })) => {
                 if path.is_ident("with") {
                     for meta in nested {
                         let NestedMeta::Meta(Meta::Path(path)) = &meta else {
@@ -1484,7 +1480,10 @@ fn extract_impl_attrs(attr: AttributeArgs, item: &Ident) -> Result<ExtractedImpl
                             )
                         } else {
                             if path.is_ident("DefaultConstructor") {
-                                bail_span!(meta, "Try `#[pyclass(with(Constructor, ...))]` instead of `#[pyclass(with(DefaultConstructor, ...))]`. DefaultConstructor implicitly implements Constructor.")
+                                bail_span!(
+                                    meta,
+                                    "Try `#[pyclass(with(Constructor, ...))]` instead of `#[pyclass(with(DefaultConstructor, ...))]`. DefaultConstructor implicitly implements Constructor."
+                                )
                             }
                             if path.is_ident("Constructor") || path.is_ident("Unconstructible") {
                                 has_constructor = true;
@@ -1523,12 +1522,16 @@ fn extract_impl_attrs(attr: AttributeArgs, item: &Ident) -> Result<ExtractedImpl
                     bail_span!(path, "Unknown pyimpl attribute")
                 }
             }
-            NestedMeta::Meta(Meta::NameValue(syn::MetaNameValue { path, lit, .. })) => {
+            NestedMeta::Meta(Meta::NameValue(syn::MetaNameValue { path, value, .. })) => {
                 if path.is_ident("payload") {
-                    if let syn::Lit::Str(lit) = lit {
+                    if let syn::Expr::Lit(syn::ExprLit {
+                        lit: syn::Lit::Str(lit),
+                        ..
+                    }) = value
+                    {
                         payload = Some(Ident::new(&lit.value(), lit.span()));
                     } else {
-                        bail_span!(lit, "payload must be a string literal")
+                        bail_span!(value, "payload must be a string literal")
                     }
                 } else {
                     bail_span!(path, "Unknown pyimpl attribute")
diff --git a/derive-impl/src/pymodule.rs b/derive-impl/src/pymodule.rs
index b9a59c8280..c59e40678e 100644
--- a/derive-impl/src/pymodule.rs
+++ b/derive-impl/src/pymodule.rs
@@ -1,14 +1,15 @@
 use crate::error::Diagnostic;
 use crate::util::{
-    format_doc, iter_use_idents, pyclass_ident_and_attrs, text_signature, AttrItemMeta,
-    AttributeExt, ClassItemMeta, ContentItem, ContentItemInner, ErrorVec, ItemMeta, ItemNursery,
-    ModuleItemMeta, SimpleItemMeta, ALL_ALLOWED_NAMES,
+    ALL_ALLOWED_NAMES, AttrItemMeta, AttributeExt, ClassItemMeta, ContentItem, ContentItemInner,
+    ErrorVec, ItemMeta, ItemNursery, ModuleItemMeta, SimpleItemMeta, format_doc, iter_use_idents,
+    pyclass_ident_and_attrs, text_signature,
 };
 use proc_macro2::{Delimiter, Group, TokenStream, TokenTree};
-use quote::{quote, quote_spanned, ToTokens};
+use quote::{ToTokens, quote, quote_spanned};
 use std::{collections::HashSet, str::FromStr};
-use syn::{parse_quote, spanned::Spanned, Attribute, AttributeArgs, Ident, Item, Result};
+use syn::{Attribute, Ident, Item, Result, parse_quote, spanned::Spanned};
 use syn_ext::ext::*;
+use syn_ext::types::PunctuatedNestedMeta;
 
 #[derive(Clone, Copy, Eq, PartialEq)]
 enum AttrName {
@@ -51,7 +52,7 @@ struct ModuleContext {
     errors: Vec<syn::Error>,
 }
 
-pub fn impl_pymodule(attr: AttributeArgs, module_item: Item) -> Result<TokenStream> {
+pub fn impl_pymodule(attr: PunctuatedNestedMeta, module_item: Item) -> Result<TokenStream> {
     let (doc, mut module_item) = match module_item {
         Item::Mod(m) => (m.attrs.doc(), m),
         other => bail_span!(other, "#[pymodule] can only be on a full module"),
@@ -687,7 +688,7 @@ impl ModuleItem for AttributeItem {
             other => {
                 return Err(
                     self.new_syn_error(other.span(), "can only be on a function, const and use")
-                )
+                );
             }
         };
 
@@ -727,7 +728,7 @@ impl ModuleItem for AttributeItem {
             (
                 quote_spanned! { ident.span() => {
                     #let_obj
-                    for name in [(#(#names,)*)] {
+                    for name in [#(#names),*] {
                         vm.__module_set_attr(module, vm.ctx.intern_str(name), obj.clone()).unwrap();
                     }
                 }},
diff --git a/derive-impl/src/pytraverse.rs b/derive-impl/src/pytraverse.rs
index 93aa233a18..728722b83a 100644
--- a/derive-impl/src/pytraverse.rs
+++ b/derive-impl/src/pytraverse.rs
@@ -1,6 +1,6 @@
 use proc_macro2::TokenStream;
 use quote::quote;
-use syn::{Attribute, DeriveInput, Field, Meta, MetaList, NestedMeta, Result};
+use syn::{Attribute, DeriveInput, Field, Result};
 
 struct TraverseAttr {
     /// set to `true` if the attribute is `#[pytraverse(skip)]`
@@ -9,47 +9,25 @@ struct TraverseAttr {
 
 const ATTR_TRAVERSE: &str = "pytraverse";
 
-/// get the `#[pytraverse(..)]` attribute from the struct
-fn valid_get_traverse_attr_from_meta_list(list: &MetaList) -> Result<TraverseAttr> {
-    let find_skip_and_only_skip = || {
-        let len = list.nested.len();
-        if len != 1 {
-            return None;
-        }
-        let mut iter = list.nested.iter();
-        // we have checked the length, so unwrap is safe
-        let first_arg = iter.next().unwrap();
-        let skip = match first_arg {
-            NestedMeta::Meta(Meta::Path(path)) => match path.is_ident("skip") {
-                true => true,
-                false => return None,
-            },
-            _ => return None,
-        };
-        Some(skip)
-    };
-    let skip = find_skip_and_only_skip().ok_or_else(|| {
-        err_span!(
-            list,
-            "only support attr is #[pytraverse(skip)], got arguments: {:?}",
-            list.nested
-        )
-    })?;
-    Ok(TraverseAttr { skip })
-}
-
 /// only accept `#[pytraverse(skip)]` for now
 fn pytraverse_arg(attr: &Attribute) -> Option<Result<TraverseAttr>> {
-    if !attr.path.is_ident(ATTR_TRAVERSE) {
+    if !attr.path().is_ident(ATTR_TRAVERSE) {
         return None;
     }
     let ret = || {
-        let parsed = attr.parse_meta()?;
-        if let Meta::List(list) = parsed {
-            valid_get_traverse_attr_from_meta_list(&list)
-        } else {
-            bail_span!(attr, "pytraverse must be a list, like #[pytraverse(skip)]")
-        }
+        let mut skip = false;
+        attr.parse_nested_meta(|meta| {
+            if meta.path.is_ident("skip") {
+                if skip {
+                    return Err(meta.error("already specified skip"));
+                }
+                skip = true;
+            } else {
+                return Err(meta.error("unknown attr"));
+            }
+            Ok(())
+        })?;
+        Ok(TraverseAttr { skip })
     };
     Some(ret())
 }
@@ -92,7 +70,7 @@ fn gen_trace_code(item: &mut DeriveInput) -> Result<TokenStream> {
         syn::Data::Struct(s) => {
             let fields = &mut s.fields;
             match fields {
-                syn::Fields::Named(ref mut fields) => {
+                syn::Fields::Named(fields) => {
                     let res: Vec<TokenStream> = fields
                         .named
                         .iter_mut()
diff --git a/derive-impl/src/util.rs b/derive-impl/src/util.rs
index f016b0d1e9..7e0eb96fb0 100644
--- a/derive-impl/src/util.rs
+++ b/derive-impl/src/util.rs
@@ -1,13 +1,11 @@
 use itertools::Itertools;
 use proc_macro2::{Span, TokenStream};
-use quote::{quote, ToTokens};
+use quote::{ToTokens, quote};
 use std::collections::{HashMap, HashSet};
-use syn::{
-    spanned::Spanned, Attribute, Ident, Meta, MetaList, NestedMeta, Result, Signature, UseTree,
-};
+use syn::{Attribute, Ident, Result, Signature, UseTree, spanned::Spanned};
 use syn_ext::{
     ext::{AttributeExt as SynAttributeExt, *},
-    types::PunctuatedNestedMeta,
+    types::*,
 };
 
 pub(crate) const ALL_ALLOWED_NAMES: &[&str] = &[
@@ -77,7 +75,7 @@ impl ItemNursery {
 
 impl ToTokens for ValidatedItemNursery {
     fn to_tokens(&self, tokens: &mut TokenStream) {
-        let mut sorted = self.0 .0.clone();
+        let mut sorted = self.0.0.clone();
         sorted.sort_by(|a, b| a.sort_order.cmp(&b.sort_order));
         tokens.extend(sorted.iter().map(|item| {
             let cfgs = &item.cfgs;
@@ -167,7 +165,11 @@ impl ItemMetaInner {
     pub fn _optional_str(&self, key: &str) -> Result<Option<String>> {
         let value = if let Some((_, meta)) = self.meta_map.get(key) {
             let Meta::NameValue(syn::MetaNameValue {
-                lit: syn::Lit::Str(lit),
+                value:
+                    syn::Expr::Lit(syn::ExprLit {
+                        lit: syn::Lit::Str(lit),
+                        ..
+                    }),
                 ..
             }) = meta
             else {
@@ -193,7 +195,11 @@ impl ItemMetaInner {
         let value = if let Some((_, meta)) = self.meta_map.get(key) {
             match meta {
                 Meta::NameValue(syn::MetaNameValue {
-                    lit: syn::Lit::Bool(lit),
+                    value:
+                        syn::Expr::Lit(syn::ExprLit {
+                            lit: syn::Lit::Bool(lit),
+                            ..
+                        }),
                     ..
                 }) => lit.value,
                 Meta::Path(_) => true,
@@ -210,7 +216,7 @@ impl ItemMetaInner {
         key: &str,
     ) -> Result<Option<impl std::iter::Iterator<Item = &'_ NestedMeta>>> {
         let value = if let Some((_, meta)) = self.meta_map.get(key) {
-            let Meta::List(syn::MetaList {
+            let Meta::List(MetaList {
                 path: _, nested, ..
             }) = meta
             else {
@@ -350,7 +356,11 @@ impl ClassItemMeta {
         if let Some((_, meta)) = inner.meta_map.get(KEY) {
             match meta {
                 Meta::NameValue(syn::MetaNameValue {
-                    lit: syn::Lit::Str(lit),
+                    value:
+                        syn::Expr::Lit(syn::ExprLit {
+                            lit: syn::Lit::Str(lit),
+                            ..
+                        }),
                     ..
                 }) => return Ok(lit.value()),
                 Meta::Path(_) => return Ok(inner.item_name()),
@@ -387,11 +397,11 @@ impl ClassItemMeta {
         let value = if let Some((_, meta)) = inner.meta_map.get(KEY) {
             match meta {
                 Meta::NameValue(syn::MetaNameValue {
-                    lit: syn::Lit::Str(lit),
+                    value: syn::Expr::Lit(syn::ExprLit{lit:syn::Lit::Str(lit),..}),
                     ..
                 }) => Ok(Some(lit.value())),
                 Meta::NameValue(syn::MetaNameValue {
-                    lit: syn::Lit::Bool(lit),
+                    value: syn::Expr::Lit(syn::ExprLit{lit:syn::Lit::Bool(lit),..}),
                     ..
                 }) => if lit.value {
                     Err(lit.span())
@@ -437,7 +447,7 @@ impl ItemMeta for ExceptionItemMeta {
         Self(ClassItemMeta(inner))
     }
     fn inner(&self) -> &ItemMetaInner {
-        &self.0 .0
+        &self.0.0
     }
 }
 
@@ -448,7 +458,11 @@ impl ExceptionItemMeta {
         if let Some((_, meta)) = inner.meta_map.get(KEY) {
             match meta {
                 Meta::NameValue(syn::MetaNameValue {
-                    lit: syn::Lit::Str(lit),
+                    value:
+                        syn::Expr::Lit(syn::ExprLit {
+                            lit: syn::Lit::Str(lit),
+                            ..
+                        }),
                     ..
                 }) => return Ok(lit.value()),
                 Meta::Path(_) => {
@@ -456,12 +470,12 @@ impl ExceptionItemMeta {
                         let type_name = inner.item_name();
                         let Some(py_name) = type_name.as_str().strip_prefix("Py") else {
                             bail_span!(
-                            inner.item_ident,
-                            "#[pyexception] expects its underlying type to be named `Py` prefixed"
-                        )
+                                inner.item_ident,
+                                "#[pyexception] expects its underlying type to be named `Py` prefixed"
+                            )
                         };
                         py_name.to_string()
-                    })
+                    });
                 }
                 _ => {}
             }
@@ -489,7 +503,7 @@ impl std::ops::Deref for ExceptionItemMeta {
 pub(crate) trait AttributeExt: SynAttributeExt {
     fn promoted_nested(&self) -> Result<PunctuatedNestedMeta>;
     fn ident_and_promoted_nested(&self) -> Result<(&Ident, PunctuatedNestedMeta)>;
-    fn try_remove_name(&mut self, name: &str) -> Result<Option<syn::NestedMeta>>;
+    fn try_remove_name(&mut self, name: &str) -> Result<Option<NestedMeta>>;
     fn fill_nested_meta<F>(&mut self, name: &str, new_item: F) -> Result<()>
     where
         F: Fn() -> NestedMeta;
@@ -512,10 +526,10 @@ impl AttributeExt for Attribute {
         Ok((self.get_ident().unwrap(), self.promoted_nested()?))
     }
 
-    fn try_remove_name(&mut self, item_name: &str) -> Result<Option<syn::NestedMeta>> {
+    fn try_remove_name(&mut self, item_name: &str) -> Result<Option<NestedMeta>> {
         self.try_meta_mut(|meta| {
             let nested = match meta {
-                Meta::List(MetaList { ref mut nested, .. }) => Ok(nested),
+                Meta::List(MetaList { nested, .. }) => Ok(nested),
                 other => Err(syn::Error::new(
                     other.span(),
                     format!(
diff --git a/derive/src/lib.rs b/derive/src/lib.rs
index 76b7e23488..97ca026e76 100644
--- a/derive/src/lib.rs
+++ b/derive/src/lib.rs
@@ -5,6 +5,7 @@
 use proc_macro::TokenStream;
 use rustpython_derive_impl as derive_impl;
 use syn::parse_macro_input;
+use syn::punctuated::Punctuated;
 
 #[proc_macro_derive(FromArgs, attributes(pyarg))]
 pub fn derive_from_args(input: TokenStream) -> TokenStream {
@@ -12,9 +13,127 @@ pub fn derive_from_args(input: TokenStream) -> TokenStream {
     derive_impl::derive_from_args(input).into()
 }
 
+/// The attribute can be applied either to a struct, trait, or impl.
+/// # Struct
+/// This implements `MaybeTraverse`, `PyClassDef`, and `StaticType` for the struct.
+/// Consider deriving `Traverse` to implement it.
+/// ## Arguments
+/// - `module`: the module which contains the class --  can be omitted if in a `#[pymodule]`.
+/// - `name`: the name of the Python class, by default it is the name of the struct.
+/// - `base`: the base class of the Python class.
+///   This does not cause inheritance of functions or attributes that must be done by a separate trait.
+/// # Impl
+/// This part implements `PyClassImpl` for the struct.
+/// This includes methods, getters/setters, etc.; only annotated methods will be included.
+/// Common functions and abilities like instantiation and `__call__` are often implemented by
+/// traits rather than in the `impl` itself; see `Constructor` and `Callable` respectively for those.
+/// ## Arguments
+/// - `name`: the name of the Python class, when no name is provided the struct name is used.
+/// - `flags`: the flags of the class, see `PyTypeFlags`.
+///     - `BASETYPE`: allows the class to be inheritable.
+///     - `IMMUTABLETYPE`: class attributes are immutable.
+/// - `with`: which trait implementations are to be included in the python class.
+/// ```rust, ignore
+/// #[pyclass(module = "mymodule", name = "MyClass", base = "BaseClass")]
+/// struct MyStruct {
+///    x: i32,
+/// }
+///
+/// impl Constructor for MyStruct {
+///     ...
+/// }
+///
+/// #[pyclass(with(Constructor))]
+/// impl MyStruct {
+///    ...
+/// }
+/// ```
+/// ## Inner markers
+/// ### pymethod/pyclassmethod/pystaticmethod
+/// `pymethod` is used to mark a method of the Python class.
+/// `pyclassmethod` is used to mark a class method.
+/// `pystaticmethod` is used to mark a static method.
+/// #### Method signature
+/// The first parameter can be either `&self` or `<var>: PyRef<Self>` for `pymethod`.
+/// The first parameter can be `cls: PyTypeRef` for `pyclassmethod`.
+/// There is no mandatory parameter for `pystaticmethod`.
+/// Both are valid and essentially the same, but the latter can yield more control.
+/// The last parameter can optionally be of the type `&VirtualMachine` to access the VM.
+/// All other values must implement `IntoPyResult`.
+/// Numeric types, `String`, `bool`, and `PyObjectRef` implement this trait,
+/// but so does any object that implements `PyValue`.
+/// Consider using `OptionalArg` for optional arguments.
+/// #### Arguments
+/// - `magic`: marks the method as a magic method: the method name is surrounded with double underscores.
+/// ```rust, ignore
+/// #[pyclass]
+/// impl MyStruct {
+///     // This will be called as the `__add__` method in Python.
+///     #[pymethod(magic)]
+///     fn add(&self, other: &Self) -> PyResult<i32> {
+///        ...
+///     }
+/// }
+/// ```
+/// - `name`: the name of the method in Python,
+///   by default it is the same as the Rust method, or surrounded by double underscores if magic is present.
+///   This overrides `magic` and the default name and cannot be used with `magic` to prevent ambiguity.
+/// ### pygetset
+/// This is used to mark a getter/setter pair.
+/// #### Arguments
+/// - `setter`: marks the method as a setter, it acts as a getter by default.
+///   Setter method names should be prefixed with `set_`.
+/// - `name`: the name of the attribute in Python, by default it is the same as the Rust method.
+/// - `magic`: marks the method as a magic method: the method name is surrounded with double underscores.
+///   This cannot be used with `name` to prevent ambiguity.
+///
+/// Ensure both the getter and setter are marked with `name` and `magic` in the same manner.
+/// #### Examples
+/// ```rust, ignore
+/// #[pyclass]
+/// impl MyStruct {
+///    #[pygetset]
+///    fn x(&self) -> PyResult<i32> {
+///       Ok(self.x.lock())
+///     }
+///    #[pygetset(setter)]
+///   fn set_x(&mut self, value: i32) -> PyResult<()> {
+///      self.x.set(value);
+///     Ok(())
+///     }
+/// }
+/// ```
+/// ### pyslot
+/// This is used to mark a slot method it should be marked by prefixing the method in rust with `slot_`.
+/// #### Arguments
+/// - name: the name of the slot method.
+/// ### pyattr
+/// ### extend_class
+/// This helps inherit attributes from a parent class.
+/// The method this is applied on should be called `extend_class_with_fields`.
+/// #### Examples
+/// ```rust, ignore
+/// #[extend_class]
+/// fn extend_class_with_fields(ctx: &Context, class: &'static Py<PyType>) {
+///     class.set_attr(
+///         identifier!(ctx, _fields),
+///         ctx.new_tuple(vec![
+///             ctx.new_str(ascii!("body")).into(),
+///             ctx.new_str(ascii!("type_ignores")).into(),
+///         ])
+///         .into(),
+///     );
+///     class.set_attr(identifier!(ctx, _attributes), ctx.new_list(vec![]).into());
+/// }
+/// ```
+/// ### pymember
+/// # Trait
+/// `#[pyclass]` on traits functions a lot like `#[pyclass]` on `impl` blocks.
+/// Note that associated functions that are annotated with `#[pymethod]` or similar **must**
+/// have a body, abstract functions should be wrapped before applying an annotation.
 #[proc_macro_attribute]
 pub fn pyclass(attr: TokenStream, item: TokenStream) -> TokenStream {
-    let attr = parse_macro_input!(attr);
+    let attr = parse_macro_input!(attr with Punctuated::parse_terminated);
     let item = parse_macro_input!(item);
     derive_impl::pyclass(attr, item).into()
 }
@@ -29,14 +148,79 @@ pub fn pyclass(attr: TokenStream, item: TokenStream) -> TokenStream {
 /// <https://github.com/python/cpython/blob/main/Objects/exceptions.c>
 #[proc_macro_attribute]
 pub fn pyexception(attr: TokenStream, item: TokenStream) -> TokenStream {
-    let attr = parse_macro_input!(attr);
+    let attr = parse_macro_input!(attr with Punctuated::parse_terminated);
     let item = parse_macro_input!(item);
     derive_impl::pyexception(attr, item).into()
 }
 
+/// This attribute must be applied to an inline module.
+/// It defines a Python module in the form a `make_module` function in the module;
+/// this has to be used in a `get_module_inits` to properly register the module.
+/// Additionally, this macro defines 'MODULE_NAME' and 'DOC' in the module.
+/// # Arguments
+/// - `name`: the name of the python module,
+///   by default, it is the name of the module, but this can be configured.
+/// ```rust, ignore
+/// // This will create a module named `mymodule`
+/// #[pymodule(name = "mymodule")]
+/// mod module {
+/// }
+/// ```
+/// - `sub`: declare the module as a submodule of another module.
+/// ```rust, ignore
+/// #[pymodule(sub)]
+/// mod submodule {
+/// }
+///
+/// #[pymodule(with(submodule))]
+/// mod mymodule {
+/// }
+/// ```
+/// - `with`: declare the list of submodules that this module contains (see `sub` for example).
+/// ## Inner markers
+/// ### pyattr
+/// `pyattr` is a multipurpose marker that can be used in a pymodule.
+/// The most common use is to mark a function or class as a part of the module.
+/// This can be done by applying it to a function or struct prior to the `#[pyfunction]` or `#[pyclass]` macro.
+/// If applied to a constant, it will be added to the module as an attribute.
+/// If applied to a function not marked with `pyfunction`,
+/// it will also be added to the module as an attribute but the value is the result of the function.
+/// If `#[pyattr(once)]` is used in this case, the function will be called once
+/// and the result will be stored using a `static_cell`.
+/// #### Examples
+/// ```rust, ignore
+/// #[pymodule]
+/// mod mymodule {
+///     #[pyattr]
+///     const MY_CONSTANT: i32 = 42;
+///     #[pyattr]
+///    fn another_constant() -> PyResult<i32> {
+///       Ok(42)
+///    }
+///   #[pyattr(once)]
+///   fn once() -> PyResult<i32> {
+///     // This will only be called once and the result will be stored.
+///     Ok(2 ** 24)
+///  }
+///
+///     #[pyattr]
+///     #[pyfunction]
+///     fn my_function(vm: &VirtualMachine) -> PyResult<()> {
+///         ...
+///     }
+/// }
+/// ```
+/// ### pyfunction
+/// This is used to create a python function.
+/// #### Function signature
+/// The last argument can optionally be of the type `&VirtualMachine` to access the VM.
+/// Refer to the `pymethod` documentation (located in the `pyclass` macro documentation)
+/// for more information on what regular argument types are permitted.
+/// #### Arguments
+/// - `name`: the name of the function in Python, by default it is the same as the associated Rust function.
 #[proc_macro_attribute]
 pub fn pymodule(attr: TokenStream, item: TokenStream) -> TokenStream {
-    let attr = parse_macro_input!(attr);
+    let attr = parse_macro_input!(attr with Punctuated::parse_terminated);
     let item = parse_macro_input!(item);
     derive_impl::pymodule(attr, item).into()
 }
@@ -61,7 +245,7 @@ impl derive_impl::Compiler for Compiler {
         mode: rustpython_compiler::Mode,
         module_name: String,
     ) -> Result<rustpython_compiler::CodeObject, Box<dyn std::error::Error>> {
-        use rustpython_compiler::{compile, CompileOpts};
+        use rustpython_compiler::{CompileOpts, compile};
         Ok(compile(source, mode, module_name, CompileOpts::default())?)
     }
 }
diff --git a/examples/call_between_rust_and_python.rs b/examples/call_between_rust_and_python.rs
index 78eef62200..576390d059 100644
--- a/examples/call_between_rust_and_python.rs
+++ b/examples/call_between_rust_and_python.rs
@@ -1,5 +1,5 @@
 use rustpython::vm::{
-    pyclass, pymodule, PyObject, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine,
+    PyObject, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine, pyclass, pymodule,
 };
 
 pub fn main() {
@@ -31,7 +31,7 @@ pub fn main() {
 #[pymodule]
 mod rust_py_module {
     use super::*;
-    use rustpython::vm::{builtins::PyList, convert::ToPyObject, PyObjectRef};
+    use rustpython::vm::{PyObjectRef, builtins::PyList, convert::ToPyObject};
 
     #[pyfunction]
     fn rust_function(
diff --git a/examples/generator.rs b/examples/generator.rs
index 010ccd3797..937687ab8f 100644
--- a/examples/generator.rs
+++ b/examples/generator.rs
@@ -1,9 +1,9 @@
 use rustpython_vm as vm;
 use std::process::ExitCode;
 use vm::{
+    Interpreter, PyResult,
     builtins::PyIntRef,
     protocol::{PyIter, PyIterReturn},
-    Interpreter, PyResult,
 };
 
 fn py_main(interp: &Interpreter) -> vm::PyResult<()> {
diff --git a/examples/package_embed.rs b/examples/package_embed.rs
index fffa98623a..975e734593 100644
--- a/examples/package_embed.rs
+++ b/examples/package_embed.rs
@@ -1,6 +1,6 @@
 use rustpython_vm as vm;
 use std::process::ExitCode;
-use vm::{builtins::PyStrRef, Interpreter};
+use vm::{Interpreter, builtins::PyStrRef};
 
 fn py_main(interp: &Interpreter) -> vm::PyResult<PyStrRef> {
     interp.enter(|vm| {
diff --git a/examples/parse_folder.rs b/examples/parse_folder.rs
index c10450e018..f54be635c8 100644
--- a/examples/parse_folder.rs
+++ b/examples/parse_folder.rs
@@ -12,7 +12,7 @@ extern crate env_logger;
 extern crate log;
 
 use clap::{App, Arg};
-use rustpython_parser::{ast, Parse};
+use rustpython_parser::{Parse, ast};
 use std::{
     path::Path,
     time::{Duration, Instant},
diff --git a/extra_tests/snippets/builtin_object.py b/extra_tests/snippets/builtin_object.py
index ef83da83e2..5a12afbf45 100644
--- a/extra_tests/snippets/builtin_object.py
+++ b/extra_tests/snippets/builtin_object.py
@@ -7,9 +7,7 @@ class MyObject:
 assert myobj == myobj
 assert not myobj != myobj
 
-object.__subclasshook__() == NotImplemented
 object.__subclasshook__(1) == NotImplemented
-object.__subclasshook__(1, 2) == NotImplemented
 
 assert MyObject().__eq__(MyObject()) == NotImplemented
 assert MyObject().__ne__(MyObject()) == NotImplemented
diff --git a/extra_tests/snippets/builtins_ctypes.py b/extra_tests/snippets/builtins_ctypes.py
new file mode 100644
index 0000000000..5bd6e5ef25
--- /dev/null
+++ b/extra_tests/snippets/builtins_ctypes.py
@@ -0,0 +1,133 @@
+import os as _os, sys as _sys
+
+from _ctypes import sizeof
+from _ctypes import _SimpleCData
+from struct import calcsize as _calcsize
+
+def create_string_buffer(init, size=None):
+    """create_string_buffer(aBytes) -> character array
+    create_string_buffer(anInteger) -> character array
+    create_string_buffer(aBytes, anInteger) -> character array
+    """
+    if isinstance(init, bytes):
+        if size is None:
+            size = len(init)+1
+        _sys.audit("ctypes.create_string_buffer", init, size)
+        buftype = c_char * size
+        buf = buftype()
+        buf.value = init
+        return buf
+    elif isinstance(init, int):
+        _sys.audit("ctypes.create_string_buffer", None, init)
+        buftype = c_char * init
+        buf = buftype()
+        return buf
+    raise TypeError(init)
+
+def _check_size(typ, typecode=None):
+    # Check if sizeof(ctypes_type) against struct.calcsize.  This
+    # should protect somewhat against a misconfigured libffi.
+    from struct import calcsize
+    if typecode is None:
+        # Most _type_ codes are the same as used in struct
+        typecode = typ._type_
+    actual, required = sizeof(typ), calcsize(typecode)
+    if actual != required:
+        raise SystemError("sizeof(%s) wrong: %d instead of %d" % \
+                          (typ, actual, required))
+
+class c_short(_SimpleCData):
+    _type_ = "h"
+_check_size(c_short)
+
+class c_ushort(_SimpleCData):
+    _type_ = "H"
+_check_size(c_ushort)
+
+class c_long(_SimpleCData):
+    _type_ = "l"
+_check_size(c_long)
+
+class c_ulong(_SimpleCData):
+    _type_ = "L"
+_check_size(c_ulong)
+
+if _calcsize("i") == _calcsize("l"):
+    # if int and long have the same size, make c_int an alias for c_long
+    c_int = c_long
+    c_uint = c_ulong
+else:
+    class c_int(_SimpleCData):
+        _type_ = "i"
+    _check_size(c_int)
+
+    class c_uint(_SimpleCData):
+        _type_ = "I"
+    _check_size(c_uint)
+
+class c_float(_SimpleCData):
+    _type_ = "f"
+_check_size(c_float)
+
+class c_double(_SimpleCData):
+    _type_ = "d"
+_check_size(c_double)
+
+class c_longdouble(_SimpleCData):
+    _type_ = "g"
+if sizeof(c_longdouble) == sizeof(c_double):
+    c_longdouble = c_double
+
+if _calcsize("l") == _calcsize("q"):
+    # if long and long long have the same size, make c_longlong an alias for c_long
+    c_longlong = c_long
+    c_ulonglong = c_ulong
+else:
+    class c_longlong(_SimpleCData):
+        _type_ = "q"
+    _check_size(c_longlong)
+
+    class c_ulonglong(_SimpleCData):
+        _type_ = "Q"
+    ##    def from_param(cls, val):
+    ##        return ('d', float(val), val)
+    ##    from_param = classmethod(from_param)
+    _check_size(c_ulonglong)
+
+class c_ubyte(_SimpleCData):
+    _type_ = "B"
+c_ubyte.__ctype_le__ = c_ubyte.__ctype_be__ = c_ubyte
+# backward compatibility:
+##c_uchar = c_ubyte
+_check_size(c_ubyte)
+
+class c_byte(_SimpleCData):
+    _type_ = "b"
+c_byte.__ctype_le__ = c_byte.__ctype_be__ = c_byte
+_check_size(c_byte)
+
+class c_char(_SimpleCData):
+    _type_ = "c"
+c_char.__ctype_le__ = c_char.__ctype_be__ = c_char
+_check_size(c_char)
+
+class c_char_p(_SimpleCData):
+    _type_ = "z"
+    def __repr__(self):
+        return "%s(%s)" % (self.__class__.__name__, c_void_p.from_buffer(self).value)
+_check_size(c_char_p, "P")
+
+class c_void_p(_SimpleCData):
+    _type_ = "P"
+c_voidp = c_void_p # backwards compatibility (to a bug)
+_check_size(c_void_p)
+
+class c_bool(_SimpleCData):
+    _type_ = "?"
+_check_size(c_bool)
+
+i = c_int(42)
+f = c_float(3.14)
+# s = create_string_buffer(b'\000' * 32)
+assert i.value == 42
+assert abs(f.value -  3.14) < 1e-06
diff --git a/extra_tests/snippets/stdlib_imghdr.py b/extra_tests/snippets/stdlib_imghdr.py
deleted file mode 100644
index 5ca524e269..0000000000
--- a/extra_tests/snippets/stdlib_imghdr.py
+++ /dev/null
@@ -1,27 +0,0 @@
-# unittest for modified imghdr.py
-# Should be replace it into https://github.com/python/cpython/blob/main/Lib/test/test_imghdr.py
-import os
-import imghdr
-
-
-TEST_FILES = (
-    #('python.png', 'png'),
-    ('python.gif', 'gif'),
-    ('python.bmp', 'bmp'),
-    ('python.ppm', 'ppm'),
-    ('python.pgm', 'pgm'),
-    ('python.pbm', 'pbm'),
-    ('python.jpg', 'jpeg'),
-    ('python.ras', 'rast'),
-    #('python.sgi', 'rgb'),
-    ('python.tiff', 'tiff'),
-    ('python.xbm', 'xbm'),
-    ('python.webp', 'webp'),
-    ('python.exr', 'exr'),
-)
-
-resource_dir = os.path.join(os.path.dirname(__file__), 'imghdrdata')
-
-for fname, expected in TEST_FILES:
-    res = imghdr.what(os.path.join(resource_dir, fname))
-    assert res == expected
\ No newline at end of file
diff --git a/extra_tests/snippets/stdlib_math.py b/extra_tests/snippets/stdlib_math.py
index 442bbc97a5..94d8c7347c 100644
--- a/extra_tests/snippets/stdlib_math.py
+++ b/extra_tests/snippets/stdlib_math.py
@@ -291,3 +291,5 @@ def assertAllNotClose(examples, *args, **kwargs):
 assert math.fmod(-3.0, NINF) == -3.0
 assert math.fmod(0.0, 3.0) == 0.0
 assert math.fmod(0.0, NINF) == 0.0
+
+assert math.gamma(1) == 1.0
diff --git a/extra_tests/snippets/stdlib_subprocess.py b/extra_tests/snippets/stdlib_subprocess.py
index 96ead76583..2e3aa7b2c1 100644
--- a/extra_tests/snippets/stdlib_subprocess.py
+++ b/extra_tests/snippets/stdlib_subprocess.py
@@ -16,7 +16,7 @@ def echo(text):
         return ["cmd", "/C", f"echo {text}"]
     def sleep(secs):
         # TODO: make work in a non-unixy environment (something with timeout.exe?)
-        return ["sleep", str(secs)]
+        return ["powershell", "/C", "sleep", str(secs)]
 
 p = subprocess.Popen(echo("test"))
 
@@ -32,7 +32,7 @@ def sleep(secs):
 assert p.poll() is None
 
 with assert_raises(subprocess.TimeoutExpired):
-	assert p.wait(1)
+    assert p.wait(1)
 
 p.wait()
 
@@ -48,17 +48,17 @@ def sleep(secs):
 p.terminate()
 p.wait()
 if is_unix:
-	assert p.returncode == -signal.SIGTERM
+    assert p.returncode == -signal.SIGTERM
 else:
-	assert p.returncode == 1
+    assert p.returncode == 1
 
 p = subprocess.Popen(sleep(2))
 p.kill()
 p.wait()
 if is_unix:
-	assert p.returncode == -signal.SIGKILL
+    assert p.returncode == -signal.SIGKILL
 else:
-	assert p.returncode == 1
+    assert p.returncode == 1
 
 p = subprocess.Popen(echo("test"), stdout=subprocess.PIPE)
 (stdout, stderr) = p.communicate()
@@ -66,4 +66,4 @@ def sleep(secs):
 
 p = subprocess.Popen(sleep(5), stdout=subprocess.PIPE)
 with assert_raises(subprocess.TimeoutExpired):
-	p.communicate(timeout=1)
+    p.communicate(timeout=1)
diff --git a/extra_tests/snippets/stdlib_xdrlib.py b/extra_tests/snippets/stdlib_xdrlib.py
deleted file mode 100644
index 681cd77467..0000000000
--- a/extra_tests/snippets/stdlib_xdrlib.py
+++ /dev/null
@@ -1,12 +0,0 @@
-# This probably will be superceeded by the python unittests when that works.
-
-import xdrlib
-
-p = xdrlib.Packer()
-p.pack_int(1337)
-
-d = p.get_buffer()
-
-print(d)
-
-# assert d == b'\x00\x00\x059'
diff --git a/extra_tests/snippets/syntax_class.py b/extra_tests/snippets/syntax_class.py
index 28d066a9e9..fb702f3304 100644
--- a/extra_tests/snippets/syntax_class.py
+++ b/extra_tests/snippets/syntax_class.py
@@ -50,7 +50,7 @@ def kungfu(x):
         assert x == 3
 
 
-assert Bar.__doc__ == " W00t "
+assert Bar.__doc__ == "W00t "
 
 bar = Bar(42)
 assert bar.get_x.__doc__ == None
@@ -147,7 +147,7 @@ class T3:
     test3
     """
 
-assert T3.__doc__ == "\n    test3\n    "
+assert T3.__doc__ == "\ntest3\n"
 
 class T4:
 
diff --git a/extra_tests/snippets/syntax_doc.py b/extra_tests/snippets/syntax_doc.py
new file mode 100644
index 0000000000..bdfc1fe778
--- /dev/null
+++ b/extra_tests/snippets/syntax_doc.py
@@ -0,0 +1,15 @@
+
+def f1():
+    """
+        x
+    \ty
+    """
+assert f1.__doc__ == '\nx\ny\n'
+
+def f2():
+    """
+\t    x
+\t\ty
+    """
+
+assert f2.__doc__ == '\nx\n    y\n'
diff --git a/extra_tests/snippets/syntax_function2.py b/extra_tests/snippets/syntax_function2.py
index ebea34fe58..dce4cb54eb 100644
--- a/extra_tests/snippets/syntax_function2.py
+++ b/extra_tests/snippets/syntax_function2.py
@@ -44,7 +44,7 @@ def f3():
     """
     pass
 
-assert f3.__doc__ == "\n    test3\n    "
+assert f3.__doc__ == "\ntest3\n"
 
 def f4():
     "test4"
diff --git a/jit/src/lib.rs b/jit/src/lib.rs
index 99bfb45c78..37f1f2a3dd 100644
--- a/jit/src/lib.rs
+++ b/jit/src/lib.rs
@@ -152,12 +152,14 @@ impl CompiledCode {
     }
 
     unsafe fn invoke_raw(&self, cif_args: &[libffi::middle::Arg]) -> Option<AbiValue> {
-        let cif = self.sig.to_cif();
-        let value = cif.call::<UnTypedAbiValue>(
-            libffi::middle::CodePtr::from_ptr(self.code as *const _),
-            cif_args,
-        );
-        self.sig.ret.as_ref().map(|ty| value.to_typed(ty))
+        unsafe {
+            let cif = self.sig.to_cif();
+            let value = cif.call::<UnTypedAbiValue>(
+                libffi::middle::CodePtr::from_ptr(self.code as *const _),
+                cif_args,
+            );
+            self.sig.ret.as_ref().map(|ty| value.to_typed(ty))
+        }
     }
 }
 
@@ -213,9 +215,9 @@ pub enum AbiValue {
 impl AbiValue {
     fn to_libffi_arg(&self) -> libffi::middle::Arg {
         match self {
-            AbiValue::Int(ref i) => libffi::middle::Arg::new(i),
-            AbiValue::Float(ref f) => libffi::middle::Arg::new(f),
-            AbiValue::Bool(ref b) => libffi::middle::Arg::new(b),
+            AbiValue::Int(i) => libffi::middle::Arg::new(i),
+            AbiValue::Float(f) => libffi::middle::Arg::new(f),
+            AbiValue::Bool(b) => libffi::middle::Arg::new(b),
         }
     }
 }
@@ -290,10 +292,12 @@ union UnTypedAbiValue {
 
 impl UnTypedAbiValue {
     unsafe fn to_typed(self, ty: &JitType) -> AbiValue {
-        match ty {
-            JitType::Int => AbiValue::Int(self.int),
-            JitType::Float => AbiValue::Float(self.float),
-            JitType::Bool => AbiValue::Bool(self.boolean != 0),
+        unsafe {
+            match ty {
+                JitType::Int => AbiValue::Int(self.int),
+                JitType::Float => AbiValue::Float(self.float),
+                JitType::Bool => AbiValue::Bool(self.boolean != 0),
+            }
         }
     }
 }
diff --git a/rustfmt.toml b/rustfmt.toml
index 3a26366d4d..f216078d96 100644
--- a/rustfmt.toml
+++ b/rustfmt.toml
@@ -1 +1 @@
-edition = "2021"
+edition = "2024"
diff --git a/src/interpreter.rs b/src/interpreter.rs
index 9d4dc4ee98..35710ae829 100644
--- a/src/interpreter.rs
+++ b/src/interpreter.rs
@@ -1,4 +1,4 @@
-use rustpython_vm::{builtins::PyModule, Interpreter, PyRef, Settings, VirtualMachine};
+use rustpython_vm::{Interpreter, PyRef, Settings, VirtualMachine, builtins::PyModule};
 
 pub type InitHook = Box<dyn FnOnce(&mut VirtualMachine)>;
 
diff --git a/src/lib.rs b/src/lib.rs
index 0e35a6ad83..b0a176acf2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -50,14 +50,14 @@ mod interpreter;
 mod settings;
 mod shell;
 
-use rustpython_vm::{scope::Scope, PyResult, VirtualMachine};
+use rustpython_vm::{PyResult, VirtualMachine, scope::Scope};
 use std::env;
 use std::io::IsTerminal;
 use std::process::ExitCode;
 
 pub use interpreter::InterpreterConfig;
 pub use rustpython_vm as vm;
-pub use settings::{opts_with_clap, InstallPipMode, RunMode};
+pub use settings::{InstallPipMode, RunMode, opts_with_clap};
 pub use shell::run_shell;
 
 /// The main cli of the `rustpython` interpreter. This function will return `std::process::ExitCode`
@@ -78,7 +78,7 @@ pub fn run(init: impl FnOnce(&mut VirtualMachine) + 'static) -> ExitCode {
     // don't translate newlines (\r\n <=> \n)
     #[cfg(windows)]
     {
-        extern "C" {
+        unsafe extern "C" {
             fn _setmode(fd: i32, flags: i32) -> i32;
         }
         unsafe {
diff --git a/src/settings.rs b/src/settings.rs
index f6b7f21f25..35114374c8 100644
--- a/src/settings.rs
+++ b/src/settings.rs
@@ -238,7 +238,9 @@ fn settings_from(matches: &ArgMatches) -> (Settings, RunMode) {
         settings.int_max_str_digits = match env::var("PYTHONINTMAXSTRDIGITS").unwrap().parse() {
             Ok(digits @ (0 | 640..)) => digits,
             _ => {
-                error!("Fatal Python error: config_init_int_max_str_digits: PYTHONINTMAXSTRDIGITS: invalid limit; must be >= 640 or 0 for unlimited.\nPython runtime state: preinitialized");
+                error!(
+                    "Fatal Python error: config_init_int_max_str_digits: PYTHONINTMAXSTRDIGITS: invalid limit; must be >= 640 or 0 for unlimited.\nPython runtime state: preinitialized"
+                );
                 std::process::exit(1);
             }
         };
diff --git a/src/shell.rs b/src/shell.rs
index 91becb0bbf..00b6710061 100644
--- a/src/shell.rs
+++ b/src/shell.rs
@@ -1,12 +1,12 @@
 mod helper;
 
-use rustpython_parser::{lexer::LexicalErrorType, ParseErrorType, Tok};
+use rustpython_parser::{ParseErrorType, Tok, lexer::LexicalErrorType};
 use rustpython_vm::{
+    AsObject, PyResult, VirtualMachine,
     builtins::PyBaseExceptionRef,
     compiler::{self, CompileError, CompileErrorType},
     readline::{Readline, ReadlineResult},
     scope::Scope,
-    AsObject, PyResult, VirtualMachine,
 };
 
 enum ShellExecResult {
diff --git a/src/shell/helper.rs b/src/shell/helper.rs
index c228dbdf65..0fe2f5ca93 100644
--- a/src/shell/helper.rs
+++ b/src/shell/helper.rs
@@ -1,8 +1,9 @@
 #![cfg_attr(target_arch = "wasm32", allow(dead_code))]
 use rustpython_vm::{
+    AsObject, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyDictRef, PyStrRef},
     function::ArgIterable,
-    identifier, AsObject, PyResult, TryFromObject, VirtualMachine,
+    identifier,
 };
 
 pub struct ShellHelper<'vm> {
@@ -107,7 +108,7 @@ impl<'vm> ShellHelper<'vm> {
             .filter(|res| {
                 res.as_ref()
                     .ok()
-                    .map_or(true, |s| s.as_str().starts_with(word_start))
+                    .is_none_or(|s| s.as_str().starts_with(word_start))
             })
             .collect::<Result<Vec<_>, _>>()
             .ok()?;
diff --git a/stdlib/Cargo.toml b/stdlib/Cargo.toml
index 934c9b5cf1..1086dea090 100644
--- a/stdlib/Cargo.toml
+++ b/stdlib/Cargo.toml
@@ -14,11 +14,10 @@ license.workspace = true
 default = ["compiler"]
 compiler = ["rustpython-vm/compiler"]
 threading = ["rustpython-common/threading", "rustpython-vm/threading"]
-zlib = ["libz-sys", "flate2/zlib"]
 bz2 = ["bzip2"]
 sqlite = ["dep:libsqlite3-sys"]
-ssl = ["openssl", "openssl-sys", "foreign-types-shared"]
-ssl-vendor = ["ssl", "openssl/vendored", "openssl-probe"]
+ssl = ["openssl", "openssl-sys", "foreign-types-shared", "openssl-probe"]
+ssl-vendor = ["ssl", "openssl/vendored"]
 
 [dependencies]
 # rustpython crates
@@ -46,16 +45,14 @@ thread_local = { workspace = true }
 
 memchr = { workspace = true }
 base64 = "0.13.0"
-csv-core = "0.1.10"
+csv-core = "0.1.11"
 dyn-clone = "1.0.10"
-libz-sys = { version = "1.1", default-features = false, optional = true }
-puruspe = "0.2.4"
+puruspe = "0.4.0"
 xml-rs = "0.8.14"
 
 # random
 rand = { workspace = true }
-rand_core = "0.6.3"
-mt19937 = "2.0.1"
+mt19937 = "3.1"
 
 # Crypto:
 digest = "0.10.3"
@@ -82,18 +79,19 @@ ucd = "0.1.1"
 # compression
 adler32 = "1.2.0"
 crc32fast = "1.3.2"
-flate2 = "1.0.28"
+flate2 = { version = "1.1", default-features = false, features = ["zlib-rs"] }
+libz-sys = { package = "libz-rs-sys", version = "0.4" }
 bzip2 = { version = "0.4", optional = true }
 
 # uuid
 [target.'cfg(not(any(target_os = "ios", target_os = "android", target_os = "windows", target_arch = "wasm32", target_os = "redox")))'.dependencies]
 mac_address = "1.1.3"
-uuid = { version = "1.1.2", features = ["v1", "fast-rng"] }
+uuid = { version = "1.1.2", features = ["v1"] }
 
 # mmap
 [target.'cfg(all(unix, not(target_arch = "wasm32")))'.dependencies]
-memmap2 = "0.5.4"
-page_size = "0.4"
+memmap2 = "0.5.10"
+page_size = "0.6"
 
 [target.'cfg(all(unix, not(target_os = "redox"), not(target_os = "ios")))'.dependencies]
 termios = "0.3.3"
@@ -102,8 +100,8 @@ termios = "0.3.3"
 rustix = { workspace = true }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-gethostname = "0.2.3"
-socket2 = { version = "0.5.6", features = ["all"] }
+gethostname = "1.0.0"
+socket2 = { version = "0.5.8", features = ["all"] }
 dns-lookup = "2"
 openssl = { version = "0.10.66", optional = true }
 openssl-sys = { version = "0.9.80", optional = true }
@@ -136,7 +134,7 @@ features = [
 ]
 
 [target.'cfg(target_os = "macos")'.dependencies]
-system-configuration = "0.5.0"
+system-configuration = "0.5.1"
 
 [lints]
 workspace = true
diff --git a/stdlib/build.rs b/stdlib/build.rs
index 0109c633d7..3eb8a2d6b6 100644
--- a/stdlib/build.rs
+++ b/stdlib/build.rs
@@ -1,5 +1,6 @@
 fn main() {
     println!(r#"cargo::rustc-check-cfg=cfg(osslconf, values("OPENSSL_NO_COMP"))"#);
+    println!(r#"cargo::rustc-check-cfg=cfg(openssl_vendored)"#);
 
     #[allow(clippy::unusual_byte_groupings)]
     let ossl_vers = [
@@ -36,4 +37,9 @@ fn main() {
             println!("cargo:rustc-cfg=osslconf=\"{conf}\"");
         }
     }
+    // it's possible for openssl-sys to link against the system openssl under certain conditions,
+    // so let the ssl module know to only perform a probe if we're actually vendored
+    if std::env::var("DEP_OPENSSL_VENDORED").is_ok_and(|s| s == "1") {
+        println!("cargo::rustc-cfg=openssl_vendored")
+    }
 }
diff --git a/stdlib/src/array.rs b/stdlib/src/array.rs
index 9bd58f8043..494e98dc1b 100644
--- a/stdlib/src/array.rs
+++ b/stdlib/src/array.rs
@@ -1,6 +1,6 @@
 // spell-checker:ignore typecode tofile tolist fromfile
 
-use rustpython_vm::{builtins::PyModule, PyRef, VirtualMachine};
+use rustpython_vm::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = array::make_module(vm);
@@ -41,6 +41,7 @@ mod array {
             str::wchar_t,
         },
         vm::{
+            AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
             atomic_func,
             builtins::{
                 PositionIterInternal, PyByteArray, PyBytes, PyBytesRef, PyDictRef, PyFloat, PyInt,
@@ -64,7 +65,6 @@ mod array {
                 AsBuffer, AsMapping, AsSequence, Comparable, Constructor, IterNext, Iterable,
                 PyComparisonOp, Representable, SelfIter,
             },
-            AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         },
     };
     use itertools::Itertools;
@@ -1528,7 +1528,7 @@ mod array {
                         2 => Some(Self::Utf16 { big_endian }),
                         4 => Some(Self::Utf32 { big_endian }),
                         _ => None,
-                    }
+                    };
                 }
                 'f' => {
                     // Copied from CPython
diff --git a/stdlib/src/binascii.rs b/stdlib/src/binascii.rs
index d348049f4c..ce3f9febd5 100644
--- a/stdlib/src/binascii.rs
+++ b/stdlib/src/binascii.rs
@@ -2,7 +2,7 @@
 
 pub(super) use decl::crc32;
 pub(crate) use decl::make_module;
-use rustpython_vm::{builtins::PyBaseExceptionRef, convert::ToPyException, VirtualMachine};
+use rustpython_vm::{VirtualMachine, builtins::PyBaseExceptionRef, convert::ToPyException};
 
 const PAD: u8 = 61u8;
 const MAXLINESIZE: usize = 76; // Excluding the CRLF
@@ -11,10 +11,10 @@ const MAXLINESIZE: usize = 76; // Excluding the CRLF
 mod decl {
     use super::{MAXLINESIZE, PAD};
     use crate::vm::{
+        PyResult, VirtualMachine,
         builtins::{PyIntRef, PyTypeRef},
         convert::ToPyException,
         function::{ArgAsciiBuffer, ArgBytesLike, OptionalArg},
-        PyResult, VirtualMachine,
     };
     use itertools::Itertools;
 
@@ -76,7 +76,7 @@ mod decl {
             let mut unhex = Vec::<u8>::with_capacity(hex_bytes.len() / 2);
             for (n1, n2) in hex_bytes.iter().tuples() {
                 if let (Some(n1), Some(n2)) = (unhex_nibble(*n1), unhex_nibble(*n2)) {
-                    unhex.push(n1 << 4 | n2);
+                    unhex.push((n1 << 4) | n2);
                 } else {
                     return Err(super::new_binascii_error(
                         "Non-hexadecimal digit found".to_owned(),
@@ -343,7 +343,7 @@ mod decl {
                         if let (Some(ch1), Some(ch2)) =
                             (unhex_nibble(buffer[idx]), unhex_nibble(buffer[idx + 1]))
                         {
-                            out_data.push(ch1 << 4 | ch2);
+                            out_data.push((ch1 << 4) | ch2);
                         }
                         idx += 2;
                     } else {
@@ -661,19 +661,19 @@ mod decl {
                 };
 
                 if res.len() < length {
-                    res.push(char_a << 2 | char_b >> 4);
+                    res.push((char_a << 2) | (char_b >> 4));
                 } else if char_a != 0 || char_b != 0 {
                     return trailing_garbage_error();
                 }
 
                 if res.len() < length {
-                    res.push((char_b & 0xf) << 4 | char_c >> 2);
+                    res.push(((char_b & 0xf) << 4) | (char_c >> 2));
                 } else if char_c != 0 {
                     return trailing_garbage_error();
                 }
 
                 if res.len() < length {
-                    res.push((char_c & 0x3) << 6 | char_d);
+                    res.push(((char_c & 0x3) << 6) | char_d);
                 } else if char_d != 0 {
                     return trailing_garbage_error();
                 }
@@ -725,8 +725,8 @@ mod decl {
                 let char_c = *chunk.get(2).unwrap_or(&0);
 
                 res.push(uu_b2a(char_a >> 2, backtick));
-                res.push(uu_b2a((char_a & 0x3) << 4 | char_b >> 4, backtick));
-                res.push(uu_b2a((char_b & 0xf) << 2 | char_c >> 6, backtick));
+                res.push(uu_b2a(((char_a & 0x3) << 4) | (char_b >> 4), backtick));
+                res.push(uu_b2a(((char_b & 0xf) << 2) | (char_c >> 6), backtick));
                 res.push(uu_b2a(char_c & 0x3f, backtick));
             }
 
@@ -751,7 +751,10 @@ impl ToPyException for Base64DecodeError {
             InvalidByte(_, _) => "Only base64 data is allowed".to_owned(),
             InvalidLastSymbol(_, PAD) => "Excess data after padding".to_owned(),
             InvalidLastSymbol(length, _) => {
-                format!("Invalid base64-encoded string: number of data characters {} cannot be 1 more than a multiple of 4", length)
+                format!(
+                    "Invalid base64-encoded string: number of data characters {} cannot be 1 more than a multiple of 4",
+                    length
+                )
             }
             InvalidLength => "Incorrect padding".to_owned(),
         };
diff --git a/stdlib/src/bisect.rs b/stdlib/src/bisect.rs
index aaab65d788..4d67ee50b9 100644
--- a/stdlib/src/bisect.rs
+++ b/stdlib/src/bisect.rs
@@ -3,9 +3,9 @@ pub(crate) use _bisect::make_module;
 #[pymodule]
 mod _bisect {
     use crate::vm::{
+        PyObjectRef, PyResult, VirtualMachine,
         function::{ArgIndex, OptionalArg},
         types::PyComparisonOp,
-        PyObjectRef, PyResult, VirtualMachine,
     };
 
     #[derive(FromArgs)]
diff --git a/stdlib/src/blake2.rs b/stdlib/src/blake2.rs
index 9b7da3327c..4209c966e8 100644
--- a/stdlib/src/blake2.rs
+++ b/stdlib/src/blake2.rs
@@ -4,7 +4,7 @@ pub(crate) use _blake2::make_module;
 
 #[pymodule]
 mod _blake2 {
-    use crate::hashlib::_hashlib::{local_blake2b, local_blake2s, BlakeHashArgs};
+    use crate::hashlib::_hashlib::{BlakeHashArgs, local_blake2b, local_blake2s};
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
     #[pyfunction]
diff --git a/stdlib/src/bz2.rs b/stdlib/src/bz2.rs
index f150b06eb8..ba74a38db1 100644
--- a/stdlib/src/bz2.rs
+++ b/stdlib/src/bz2.rs
@@ -6,13 +6,13 @@ pub(crate) use _bz2::make_module;
 mod _bz2 {
     use crate::common::lock::PyMutex;
     use crate::vm::{
+        VirtualMachine,
         builtins::{PyBytesRef, PyTypeRef},
         function::{ArgBytesLike, OptionalArg},
         object::{PyPayload, PyResult},
         types::Constructor,
-        VirtualMachine,
     };
-    use bzip2::{write::BzEncoder, Decompress, Status};
+    use bzip2::{Decompress, Status, write::BzEncoder};
     use std::{fmt, io::Write};
 
     // const BUFSIZ: i32 = 8192;
@@ -196,7 +196,7 @@ mod _bz2 {
                 _ => {
                     return Err(
                         vm.new_value_error("compresslevel must be between 1 and 9".to_owned())
-                    )
+                    );
                 }
             };
 
diff --git a/stdlib/src/cmath.rs b/stdlib/src/cmath.rs
index c5badcf72a..4611ea344e 100644
--- a/stdlib/src/cmath.rs
+++ b/stdlib/src/cmath.rs
@@ -4,8 +4,8 @@ pub(crate) use cmath::make_module;
 #[pymodule]
 mod cmath {
     use crate::vm::{
-        function::{ArgIntoComplex, ArgIntoFloat, OptionalArg},
         PyResult, VirtualMachine,
+        function::{ArgIntoComplex, ArgIntoFloat, OptionalArg},
     };
     use num_complex::Complex64;
 
diff --git a/stdlib/src/contextvars.rs b/stdlib/src/contextvars.rs
index 40a59050b3..1e27b8b9e5 100644
--- a/stdlib/src/contextvars.rs
+++ b/stdlib/src/contextvars.rs
@@ -1,4 +1,4 @@
-use crate::vm::{builtins::PyModule, class::StaticType, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule, class::StaticType};
 use _contextvars::PyContext;
 use std::cell::RefCell;
 
@@ -23,14 +23,13 @@ thread_local! {
 #[pymodule]
 mod _contextvars {
     use crate::vm::{
-        atomic_func,
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine, atomic_func,
         builtins::{PyStrRef, PyTypeRef},
         class::StaticType,
         common::hash::PyHash,
         function::{ArgCallable, FuncArgs, OptionalArg},
         protocol::{PyMappingMethods, PySequenceMethods},
         types::{AsMapping, AsSequence, Constructor, Hashable, Representable},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use indexmap::IndexMap;
diff --git a/stdlib/src/csv.rs b/stdlib/src/csv.rs
index 2dd7f2ae12..03a5429ba4 100644
--- a/stdlib/src/csv.rs
+++ b/stdlib/src/csv.rs
@@ -4,11 +4,11 @@ pub(crate) use _csv::make_module;
 mod _csv {
     use crate::common::lock::PyMutex;
     use crate::vm::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyInt, PyNone, PyStr, PyType, PyTypeError, PyTypeRef},
         function::{ArgIterable, ArgumentError, FromArgs, FuncArgs, OptionalArg},
         protocol::{PyIter, PyIterReturn},
         types::{Constructor, IterNext, Iterable, SelfIter},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
     use csv_core::Terminator;
     use itertools::{self, Itertools};
@@ -272,12 +272,12 @@ mod _csv {
         let Some(name) = name.payload_if_subclass::<PyStr>(vm) else {
             return Err(vm.new_type_error("argument 0 must be a string".to_string()));
         };
-        let mut dialect = match dialect {
+        let dialect = match dialect {
             OptionalArg::Present(d) => PyDialect::try_from_object(vm, d)
                 .map_err(|_| vm.new_type_error("argument 1 must be a dialect object".to_owned()))?,
             OptionalArg::Missing => opts.result(vm)?,
         };
-        opts.update_pydialect(&mut dialect);
+        let dialect = opts.update_pydialect(dialect);
         GLOBAL_HASHMAP
             .lock()
             .insert(name.as_str().to_owned(), dialect);
@@ -396,7 +396,7 @@ mod _csv {
             Some(write_meth) => write_meth,
             None if file.is_callable() => file,
             None => {
-                return Err(vm.new_type_error("argument 1 must have a \"write\" method".to_owned()))
+                return Err(vm.new_type_error("argument 1 must have a \"write\" method".to_owned()));
             }
         };
 
@@ -665,7 +665,7 @@ mod _csv {
     }
 
     impl FormatOptions {
-        fn update_pydialect<'b>(&self, res: &'b mut PyDialect) -> &'b mut PyDialect {
+        fn update_pydialect(&self, mut res: PyDialect) -> PyDialect {
             macro_rules! check_and_fill {
                 ($res:ident, $e:ident) => {{
                     if let Some(t) = self.$e {
@@ -699,24 +699,18 @@ mod _csv {
                 DialectItem::Str(name) => {
                     let g = GLOBAL_HASHMAP.lock();
                     if let Some(dialect) = g.get(name) {
-                        let mut dialect = *dialect;
-                        self.update_pydialect(&mut dialect);
-                        Ok(dialect)
+                        Ok(self.update_pydialect(*dialect))
                     } else {
                         Err(new_csv_error(vm, format!("{} is not registed.", name)))
                     }
                     // TODO
                     // Maybe need to update the obj from HashMap
                 }
-                DialectItem::Obj(mut o) => {
-                    self.update_pydialect(&mut o);
-                    Ok(o)
-                }
+                DialectItem::Obj(o) => Ok(self.update_pydialect(*o)),
                 DialectItem::None => {
                     let g = GLOBAL_HASHMAP.lock();
-                    let mut res = *g.get("excel").unwrap();
-                    self.update_pydialect(&mut res);
-                    Ok(res)
+                    let res = *g.get("excel").unwrap();
+                    Ok(self.update_pydialect(res))
                 }
             }
         }
@@ -1001,7 +995,7 @@ mod _csv {
                     csv_core::ReadRecordResult::OutputEndsFull => resize_buf(output_ends),
                     csv_core::ReadRecordResult::Record => break,
                     csv_core::ReadRecordResult::End => {
-                        return Ok(PyIterReturn::StopIteration(None))
+                        return Ok(PyIterReturn::StopIteration(None));
                     }
                 }
             }
diff --git a/stdlib/src/dis.rs b/stdlib/src/dis.rs
index 12c2ea75df..69767ffbba 100644
--- a/stdlib/src/dis.rs
+++ b/stdlib/src/dis.rs
@@ -3,9 +3,9 @@ pub(crate) use decl::make_module;
 #[pymodule(name = "dis")]
 mod decl {
     use crate::vm::{
+        PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyCode, PyDictRef, PyStrRef},
         bytecode::CodeFlags,
-        PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
 
     #[pyfunction]
diff --git a/stdlib/src/faulthandler.rs b/stdlib/src/faulthandler.rs
index 2fb93ecc88..9ffd931291 100644
--- a/stdlib/src/faulthandler.rs
+++ b/stdlib/src/faulthandler.rs
@@ -2,7 +2,7 @@ pub(crate) use decl::make_module;
 
 #[pymodule(name = "faulthandler")]
 mod decl {
-    use crate::vm::{frame::Frame, function::OptionalArg, stdlib::sys::PyStderr, VirtualMachine};
+    use crate::vm::{VirtualMachine, frame::Frame, function::OptionalArg, stdlib::sys::PyStderr};
 
     fn dump_frame(frame: &Frame, vm: &VirtualMachine) {
         let stderr = PyStderr(vm);
diff --git a/stdlib/src/fcntl.rs b/stdlib/src/fcntl.rs
index ee73e50397..307d6e4351 100644
--- a/stdlib/src/fcntl.rs
+++ b/stdlib/src/fcntl.rs
@@ -3,10 +3,10 @@ pub(crate) use fcntl::make_module;
 #[pymodule]
 mod fcntl {
     use crate::vm::{
+        PyResult, VirtualMachine,
         builtins::PyIntRef,
         function::{ArgMemoryBuffer, ArgStrOrBytesLike, Either, OptionalArg},
         stdlib::{io, os},
-        PyResult, VirtualMachine,
     };
 
     // TODO: supply these from <asm-generic/fnctl.h> (please file an issue/PR upstream):
@@ -20,7 +20,7 @@ mod fcntl {
     //       I_LINK, I_UNLINK, I_PLINK, I_PUNLINK
 
     #[pyattr]
-    use libc::{FD_CLOEXEC, F_GETFD, F_GETFL, F_SETFD, F_SETFL};
+    use libc::{F_GETFD, F_GETFL, F_SETFD, F_SETFL, FD_CLOEXEC};
 
     #[cfg(not(target_os = "wasi"))]
     #[pyattr]
@@ -45,7 +45,7 @@ mod fcntl {
     #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
     #[pyattr]
     use libc::{
-        F_ADD_SEALS, F_GETLEASE, F_GETPIPE_SZ, F_GET_SEALS, F_NOTIFY, F_SEAL_GROW, F_SEAL_SEAL,
+        F_ADD_SEALS, F_GET_SEALS, F_GETLEASE, F_GETPIPE_SZ, F_NOTIFY, F_SEAL_GROW, F_SEAL_SEAL,
         F_SEAL_SHRINK, F_SEAL_WRITE, F_SETLEASE, F_SETPIPE_SZ,
     };
 
diff --git a/stdlib/src/gc.rs b/stdlib/src/gc.rs
index c78eea9c29..6e906ebab2 100644
--- a/stdlib/src/gc.rs
+++ b/stdlib/src/gc.rs
@@ -2,7 +2,7 @@ pub(crate) use gc::make_module;
 
 #[pymodule]
 mod gc {
-    use crate::vm::{function::FuncArgs, PyResult, VirtualMachine};
+    use crate::vm::{PyResult, VirtualMachine, function::FuncArgs};
 
     #[pyfunction]
     fn collect(_args: FuncArgs, _vm: &VirtualMachine) -> i32 {
diff --git a/stdlib/src/grp.rs b/stdlib/src/grp.rs
index d3eb0848bb..2cdad56588 100644
--- a/stdlib/src/grp.rs
+++ b/stdlib/src/grp.rs
@@ -3,11 +3,11 @@ pub(crate) use grp::make_module;
 #[pymodule]
 mod grp {
     use crate::vm::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::{PyIntRef, PyListRef, PyStrRef},
         convert::{IntoPyException, ToPyObject},
         exceptions,
         types::PyStructSequence,
-        PyObjectRef, PyResult, VirtualMachine,
     };
     use nix::unistd;
     use std::ptr::NonNull;
diff --git a/stdlib/src/hashlib.rs b/stdlib/src/hashlib.rs
index 6944c37f9d..6124b6d242 100644
--- a/stdlib/src/hashlib.rs
+++ b/stdlib/src/hashlib.rs
@@ -6,16 +6,16 @@ pub(crate) use _hashlib::make_module;
 pub mod _hashlib {
     use crate::common::lock::PyRwLock;
     use crate::vm::{
+        PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyBytes, PyStrRef, PyTypeRef},
         convert::ToPyObject,
         function::{ArgBytesLike, ArgStrOrBytesLike, FuncArgs, OptionalArg},
         protocol::PyBuffer,
-        PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     use blake2::{Blake2b512, Blake2s256};
-    use digest::{core_api::BlockSizeUser, DynDigest};
+    use digest::{DynDigest, core_api::BlockSizeUser};
     use digest::{ExtendableOutput, Update};
-    use dyn_clone::{clone_trait_object, DynClone};
+    use dyn_clone::{DynClone, clone_trait_object};
     use md5::Md5;
     use sha1::Sha1;
     use sha2::{Sha224, Sha256, Sha384, Sha512};
diff --git a/stdlib/src/json.rs b/stdlib/src/json.rs
index 921e545e5d..aaac0b8bef 100644
--- a/stdlib/src/json.rs
+++ b/stdlib/src/json.rs
@@ -5,12 +5,12 @@ mod machinery;
 mod _json {
     use super::machinery;
     use crate::vm::{
+        AsObject, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyStrRef, PyType, PyTypeRef},
         convert::{ToPyObject, ToPyResult},
         function::{IntoFuncArgs, OptionalArg},
         protocol::PyIterReturn,
         types::{Callable, Constructor},
-        AsObject, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     use malachite_bigint::BigInt;
     use std::str::FromStr;
@@ -80,14 +80,14 @@ mod _json {
                 None => {
                     return Ok(PyIterReturn::StopIteration(Some(
                         vm.ctx.new_int(idx).into(),
-                    )))
+                    )));
                 }
             };
             let next_idx = idx + c.len_utf8();
             match c {
                 '"' => {
                     return scanstring(pystr, next_idx, OptionalArg::Present(self.strict), vm)
-                        .map(|x| PyIterReturn::Return(x.to_pyobject(vm)))
+                        .map(|x| PyIterReturn::Return(x.to_pyobject(vm)));
                 }
                 '{' => {
                     // TODO: parse the object in rust
diff --git a/stdlib/src/json/machinery.rs b/stdlib/src/json/machinery.rs
index fc6b530866..0614314f4f 100644
--- a/stdlib/src/json/machinery.rs
+++ b/stdlib/src/json/machinery.rs
@@ -135,7 +135,7 @@ pub fn scanstring<'a>(
     };
     let unterminated_err = || DecodeError::new("Unterminated string starting at", end - 1);
     let mut chars = s.char_indices().enumerate().skip(end).peekable();
-    let (_, (mut chunk_start, _)) = chars.peek().ok_or_else(unterminated_err)?;
+    let &(_, (mut chunk_start, _)) = chars.peek().ok_or_else(unterminated_err)?;
     while let Some((char_i, (byte_i, c))) = chars.next() {
         match c {
             '"' => {
diff --git a/stdlib/src/locale.rs b/stdlib/src/locale.rs
index bbe1008e53..9ca71a0957 100644
--- a/stdlib/src/locale.rs
+++ b/stdlib/src/locale.rs
@@ -30,7 +30,7 @@ struct lconv {
 }
 
 #[cfg(windows)]
-extern "C" {
+unsafe extern "C" {
     fn localeconv() -> *mut lconv;
 }
 
@@ -40,10 +40,10 @@ use libc::localeconv;
 #[pymodule]
 mod _locale {
     use rustpython_vm::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::{PyDictRef, PyIntRef, PyListRef, PyStrRef, PyTypeRef},
         convert::ToPyException,
         function::OptionalArg,
-        PyObjectRef, PyResult, VirtualMachine,
     };
     use std::{
         ffi::{CStr, CString},
@@ -56,12 +56,12 @@ mod _locale {
     ))]
     #[pyattr]
     use libc::{
-        ABDAY_1, ABDAY_2, ABDAY_3, ABDAY_4, ABDAY_5, ABDAY_6, ABDAY_7, ABMON_1, ABMON_10, ABMON_11,
-        ABMON_12, ABMON_2, ABMON_3, ABMON_4, ABMON_5, ABMON_6, ABMON_7, ABMON_8, ABMON_9,
-        ALT_DIGITS, AM_STR, CODESET, CRNCYSTR, DAY_1, DAY_2, DAY_3, DAY_4, DAY_5, DAY_6, DAY_7,
-        D_FMT, D_T_FMT, ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, LC_MESSAGES, MON_1, MON_10, MON_11,
-        MON_12, MON_2, MON_3, MON_4, MON_5, MON_6, MON_7, MON_8, MON_9, NOEXPR, PM_STR, RADIXCHAR,
-        THOUSEP, T_FMT, T_FMT_AMPM, YESEXPR,
+        ABDAY_1, ABDAY_2, ABDAY_3, ABDAY_4, ABDAY_5, ABDAY_6, ABDAY_7, ABMON_1, ABMON_2, ABMON_3,
+        ABMON_4, ABMON_5, ABMON_6, ABMON_7, ABMON_8, ABMON_9, ABMON_10, ABMON_11, ABMON_12,
+        ALT_DIGITS, AM_STR, CODESET, CRNCYSTR, D_FMT, D_T_FMT, DAY_1, DAY_2, DAY_3, DAY_4, DAY_5,
+        DAY_6, DAY_7, ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, LC_MESSAGES, MON_1, MON_2, MON_3,
+        MON_4, MON_5, MON_6, MON_7, MON_8, MON_9, MON_10, MON_11, MON_12, NOEXPR, PM_STR,
+        RADIXCHAR, T_FMT, T_FMT_AMPM, THOUSEP, YESEXPR,
     };
 
     #[pyattr]
@@ -78,11 +78,13 @@ mod _locale {
             return vm.ctx.new_list(group_vec);
         }
 
-        let mut ptr = group;
-        while ![0, libc::c_char::MAX].contains(&*ptr) {
-            let val = vm.ctx.new_int(*ptr);
-            group_vec.push(val.into());
-            ptr = ptr.add(1);
+        unsafe {
+            let mut ptr = group;
+            while ![0, libc::c_char::MAX].contains(&*ptr) {
+                let val = vm.ctx.new_int(*ptr);
+                group_vec.push(val.into());
+                ptr = ptr.add(1);
+            }
         }
         // https://github.com/python/cpython/blob/677320348728ce058fa3579017e985af74a236d4/Modules/_localemodule.c#L80
         if !group_vec.is_empty() {
@@ -146,9 +148,7 @@ mod _locale {
             }
 
             macro_rules! set_int_field {
-                ($lc:expr, $field:ident) => {{
-                    result.set_item(stringify!($field), vm.new_pyobj((*$lc).$field), vm)?
-                }};
+                ($lc:expr, $field:ident) => {{ result.set_item(stringify!($field), vm.new_pyobj((*$lc).$field), vm)? }};
             }
 
             macro_rules! set_group_field {
diff --git a/stdlib/src/math.rs b/stdlib/src/math.rs
index c1abc1a6f2..f86ebb591e 100644
--- a/stdlib/src/math.rs
+++ b/stdlib/src/math.rs
@@ -3,9 +3,10 @@ pub(crate) use math::make_module;
 #[pymodule]
 mod math {
     use crate::vm::{
-        builtins::{try_bigint_to_f64, try_f64_to_bigint, PyFloat, PyInt, PyIntRef, PyStrInterned},
+        PyObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
+        builtins::{PyFloat, PyInt, PyIntRef, PyStrInterned, try_bigint_to_f64, try_f64_to_bigint},
         function::{ArgIndex, ArgIntoFloat, ArgIterable, Either, OptionalArg, PosArgs},
-        identifier, PyObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
+        identifier,
     };
     use itertools::Itertools;
     use malachite_bigint::BigInt;
@@ -132,6 +133,9 @@ mod math {
     #[pyfunction]
     fn log(x: PyObjectRef, base: OptionalArg<ArgIntoFloat>, vm: &VirtualMachine) -> PyResult<f64> {
         let base = base.map(|b| *b).unwrap_or(std::f64::consts::E);
+        if base.is_sign_negative() {
+            return Err(vm.new_value_error("math domain error".to_owned()));
+        }
         log2(x, vm).map(|logx| logx / base.log2())
     }
 
@@ -192,16 +196,18 @@ mod math {
         let x = *x;
         let y = *y;
 
-        if x < 0.0 && x.is_finite() && y.fract() != 0.0 && y.is_finite() {
-            return Err(vm.new_value_error("math domain error".to_owned()));
-        }
-
-        if x == 0.0 && y < 0.0 && y != f64::NEG_INFINITY {
+        if x < 0.0 && x.is_finite() && y.fract() != 0.0 && y.is_finite()
+            || x == 0.0 && y < 0.0 && y != f64::NEG_INFINITY
+        {
             return Err(vm.new_value_error("math domain error".to_owned()));
         }
 
         let value = x.powf(y);
 
+        if x.is_finite() && y.is_finite() && value.is_infinite() {
+            return Err(vm.new_overflow_error("math range error".to_string()));
+        }
+
         Ok(value)
     }
 
@@ -212,6 +218,9 @@ mod math {
             return Ok(value);
         }
         if value.is_sign_negative() {
+            if value.is_zero() {
+                return Ok(-0.0f64);
+            }
             return Err(vm.new_value_error("math domain error".to_owned()));
         }
         Ok(value.sqrt())
@@ -260,6 +269,9 @@ mod math {
 
     #[pyfunction]
     fn cos(x: ArgIntoFloat, vm: &VirtualMachine) -> PyResult<f64> {
+        if x.is_infinite() {
+            return Err(vm.new_value_error("math domain error".to_owned()));
+        }
         call_math_func!(cos, x, vm)
     }
 
@@ -345,7 +357,7 @@ mod math {
                 .map(|x| (x / scale).powi(2))
                 .chain(std::iter::once(-norm * norm))
                 // Pairwise summation of floats gives less rounding error than a naive sum.
-                .tree_fold1(std::ops::Add::add)
+                .tree_reduce(std::ops::Add::add)
                 .expect("expected at least 1 element");
             norm = norm + correction / (2.0 * norm);
         }
@@ -394,11 +406,17 @@ mod math {
 
     #[pyfunction]
     fn sin(x: ArgIntoFloat, vm: &VirtualMachine) -> PyResult<f64> {
+        if x.is_infinite() {
+            return Err(vm.new_value_error("math domain error".to_owned()));
+        }
         call_math_func!(sin, x, vm)
     }
 
     #[pyfunction]
     fn tan(x: ArgIntoFloat, vm: &VirtualMachine) -> PyResult<f64> {
+        if x.is_infinite() {
+            return Err(vm.new_value_error("math domain error".to_owned()));
+        }
         call_math_func!(tan, x, vm)
     }
 
@@ -458,21 +476,13 @@ mod math {
     #[pyfunction]
     fn erf(x: ArgIntoFloat) -> f64 {
         let x = *x;
-        if x.is_nan() {
-            x
-        } else {
-            puruspe::erf(x)
-        }
+        if x.is_nan() { x } else { puruspe::erf(x) }
     }
 
     #[pyfunction]
     fn erfc(x: ArgIntoFloat) -> f64 {
         let x = *x;
-        if x.is_nan() {
-            x
-        } else {
-            puruspe::erfc(x)
-        }
+        if x.is_nan() { x } else { puruspe::erfc(x) }
     }
 
     #[pyfunction]
@@ -612,7 +622,7 @@ mod math {
 
     #[pyfunction]
     fn fsum(seq: ArgIterable<ArgIntoFloat>, vm: &VirtualMachine) -> PyResult<f64> {
-        let mut partials = vec![];
+        let mut partials = Vec::with_capacity(32);
         let mut special_sum = 0.0;
         let mut inf_sum = 0.0;
 
@@ -620,11 +630,11 @@ mod math {
             let mut x = *obj?;
 
             let xsave = x;
-            let mut j = 0;
+            let mut i = 0;
             // This inner loop applies `hi`/`lo` summation to each
             // partial so that the list of partial sums remains exact.
-            for i in 0..partials.len() {
-                let mut y: f64 = partials[i];
+            for j in 0..partials.len() {
+                let mut y: f64 = partials[j];
                 if x.abs() < y.abs() {
                     std::mem::swap(&mut x, &mut y);
                 }
@@ -633,33 +643,33 @@ mod math {
                 let hi = x + y;
                 let lo = y - (hi - x);
                 if lo != 0.0 {
-                    partials[j] = lo;
-                    j += 1;
+                    partials[i] = lo;
+                    i += 1;
                 }
                 x = hi;
             }
 
-            if !x.is_finite() {
-                // a nonfinite x could arise either as
-                // a result of intermediate overflow, or
-                // as a result of a nan or inf in the
-                // summands
-                if xsave.is_finite() {
-                    return Err(vm.new_overflow_error("intermediate overflow in fsum".to_owned()));
-                }
-                if xsave.is_infinite() {
-                    inf_sum += xsave;
+            partials.truncate(i);
+            if x != 0.0 {
+                if !x.is_finite() {
+                    // a nonfinite x could arise either as
+                    // a result of intermediate overflow, or
+                    // as a result of a nan or inf in the
+                    // summands
+                    if xsave.is_finite() {
+                        return Err(
+                            vm.new_overflow_error("intermediate overflow in fsum".to_owned())
+                        );
+                    }
+                    if xsave.is_infinite() {
+                        inf_sum += xsave;
+                    }
+                    special_sum += xsave;
+                    // reset partials
+                    partials.clear();
+                } else {
+                    partials.push(x);
                 }
-                special_sum += xsave;
-                // reset partials
-                partials.clear();
-            }
-
-            if j >= partials.len() {
-                partials.push(x);
-            } else {
-                partials[j] = x;
-                partials.truncate(j + 1);
             }
         }
         if special_sum != 0.0 {
@@ -814,9 +824,38 @@ mod math {
         (x.fract(), x.trunc())
     }
 
-    #[pyfunction]
-    fn nextafter(x: ArgIntoFloat, y: ArgIntoFloat) -> f64 {
-        float_ops::nextafter(*x, *y)
+    #[derive(FromArgs)]
+    struct NextAfterArgs {
+        #[pyarg(positional)]
+        x: ArgIntoFloat,
+        #[pyarg(positional)]
+        y: ArgIntoFloat,
+        #[pyarg(named, optional)]
+        steps: OptionalArg<ArgIndex>,
+    }
+
+    #[pyfunction]
+    fn nextafter(arg: NextAfterArgs, vm: &VirtualMachine) -> PyResult<f64> {
+        let steps: Option<i64> = arg
+            .steps
+            .map(|v| v.try_to_primitive(vm))
+            .transpose()?
+            .into_option();
+        match steps {
+            Some(steps) => {
+                if steps < 0 {
+                    return Err(
+                        vm.new_value_error("steps must be a non-negative integer".to_string())
+                    );
+                }
+                Ok(float_ops::nextafter_with_steps(
+                    *arg.x,
+                    *arg.y,
+                    steps as u64,
+                ))
+            }
+            None => Ok(float_ops::nextafter(*arg.x, *arg.y)),
+        }
     }
 
     #[pyfunction]
@@ -900,10 +939,38 @@ mod math {
         // refer: https://github.com/python/cpython/blob/main/Modules/mathmodule.c#L3093-L3193
         for obj in iter.iter(vm)? {
             let obj = obj?;
+            result = vm._mul(&result, &obj)?;
+        }
+
+        Ok(result)
+    }
 
-            result = vm
-                ._mul(&result, &obj)
-                .map_err(|_| vm.new_type_error("math type error".to_owned()))?;
+    #[pyfunction]
+    fn sumprod(
+        p: ArgIterable<PyObjectRef>,
+        q: ArgIterable<PyObjectRef>,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyObjectRef> {
+        let mut p_iter = p.iter(vm)?;
+        let mut q_iter = q.iter(vm)?;
+        // We cannot just create a float because the iterator may contain
+        // anything as long as it supports __add__ and __mul__.
+        let mut result = vm.new_pyobj(0);
+        loop {
+            let m_p = p_iter.next();
+            let m_q = q_iter.next();
+            match (m_p, m_q) {
+                (Some(r_p), Some(r_q)) => {
+                    let p = r_p?;
+                    let q = r_q?;
+                    let tmp = vm._mul(&p, &q)?;
+                    result = vm._add(&result, &tmp)?;
+                }
+                (None, None) => break,
+                _ => {
+                    return Err(vm.new_value_error("Inputs are not the same length".to_string()));
+                }
+            }
         }
 
         Ok(result)
diff --git a/stdlib/src/md5.rs b/stdlib/src/md5.rs
index 833d217f5b..dca48242bb 100644
--- a/stdlib/src/md5.rs
+++ b/stdlib/src/md5.rs
@@ -2,7 +2,7 @@ pub(crate) use _md5::make_module;
 
 #[pymodule]
 mod _md5 {
-    use crate::hashlib::_hashlib::{local_md5, HashArgs};
+    use crate::hashlib::_hashlib::{HashArgs, local_md5};
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
     #[pyfunction]
diff --git a/stdlib/src/mmap.rs b/stdlib/src/mmap.rs
index 8b657532c4..e96339c370 100644
--- a/stdlib/src/mmap.rs
+++ b/stdlib/src/mmap.rs
@@ -8,7 +8,8 @@ mod mmap {
         lock::{MapImmutable, PyMutex, PyMutexGuard},
     };
     use crate::vm::{
-        atomic_func,
+        AsObject, FromArgs, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+        TryFromBorrowedObject, VirtualMachine, atomic_func,
         builtins::{PyBytes, PyBytesRef, PyInt, PyIntRef, PyTypeRef},
         byte::{bytes_from_object, value_from_object},
         convert::ToPyException,
@@ -18,8 +19,6 @@ mod mmap {
         },
         sliceable::{SaturatedSlice, SequenceIndex, SequenceIndexOp},
         types::{AsBuffer, AsMapping, AsSequence, Constructor, Representable},
-        AsObject, FromArgs, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-        TryFromBorrowedObject, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use memmap2::{Advice, Mmap, MmapMut, MmapOptions};
@@ -497,8 +496,8 @@ mod mmap {
         fn as_bytes(&self) -> BorrowedValue<[u8]> {
             PyMutexGuard::map_immutable(self.mmap.lock(), |m| {
                 match m.as_ref().expect("mmap closed or invalid") {
-                    MmapObj::Read(ref mmap) => &mmap[..],
-                    MmapObj::Write(ref mmap) => &mmap[..],
+                    MmapObj::Read(mmap) => &mmap[..],
+                    MmapObj::Write(mmap) => &mmap[..],
                 }
             })
             .into()
diff --git a/stdlib/src/multiprocessing.rs b/stdlib/src/multiprocessing.rs
index a6d902eb63..2db922e16b 100644
--- a/stdlib/src/multiprocessing.rs
+++ b/stdlib/src/multiprocessing.rs
@@ -3,7 +3,7 @@ pub(crate) use _multiprocessing::make_module;
 #[cfg(windows)]
 #[pymodule]
 mod _multiprocessing {
-    use crate::vm::{function::ArgBytesLike, stdlib::os, PyResult, VirtualMachine};
+    use crate::vm::{PyResult, VirtualMachine, function::ArgBytesLike, stdlib::os};
     use windows_sys::Win32::Networking::WinSock::{self, SOCKET};
 
     #[pyfunction]
diff --git a/stdlib/src/overlapped.rs b/stdlib/src/overlapped.rs
index 9d08d88bcd..45eac5f51b 100644
--- a/stdlib/src/overlapped.rs
+++ b/stdlib/src/overlapped.rs
@@ -6,13 +6,13 @@ mod _overlapped {
     // straight-forward port of Modules/overlapped.c
 
     use crate::vm::{
+        Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyBytesRef, PyTypeRef},
         common::lock::PyMutex,
         convert::{ToPyException, ToPyObject},
         protocol::PyBuffer,
         stdlib::os::errno_err,
         types::Constructor,
-        Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     use windows_sys::Win32::{
         Foundation::{self, GetLastError, HANDLE},
diff --git a/stdlib/src/posixsubprocess.rs b/stdlib/src/posixsubprocess.rs
index 64e897b607..cff00a70aa 100644
--- a/stdlib/src/posixsubprocess.rs
+++ b/stdlib/src/posixsubprocess.rs
@@ -28,7 +28,7 @@ mod _posixsubprocess {
     use rustpython_vm::{AsObject, TryFromBorrowedObject};
 
     use super::*;
-    use crate::vm::{convert::IntoPyException, PyResult, VirtualMachine};
+    use crate::vm::{PyResult, VirtualMachine, convert::IntoPyException};
 
     #[pyfunction]
     fn fork_exec(args: ForkExecArgs, vm: &VirtualMachine) -> PyResult<libc::pid_t> {
diff --git a/stdlib/src/pyexpat.rs b/stdlib/src/pyexpat.rs
index 89267d3f7e..3cfe048f17 100644
--- a/stdlib/src/pyexpat.rs
+++ b/stdlib/src/pyexpat.rs
@@ -3,7 +3,7 @@
 *
 */
 
-use crate::vm::{builtins::PyModule, extend_module, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule, extend_module};
 
 pub fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = _pyexpat::make_module(vm);
@@ -32,10 +32,10 @@ macro_rules! create_property {
 #[pymodule(name = "pyexpat")]
 mod _pyexpat {
     use crate::vm::{
+        Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyStr, PyStrRef, PyType},
         function::ArgBytesLike,
         function::{IntoFuncArgs, OptionalArg},
-        Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
     use rustpython_common::lock::PyRwLock;
     use std::io::Cursor;
diff --git a/stdlib/src/pystruct.rs b/stdlib/src/pystruct.rs
index 2d83e9570d..f8d41414f7 100644
--- a/stdlib/src/pystruct.rs
+++ b/stdlib/src/pystruct.rs
@@ -10,13 +10,13 @@ pub(crate) use _struct::make_module;
 #[pymodule]
 pub(crate) mod _struct {
     use crate::vm::{
-        buffer::{new_struct_error, struct_error_type, FormatSpec},
+        AsObject, Py, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
+        buffer::{FormatSpec, new_struct_error, struct_error_type},
         builtins::{PyBytes, PyStr, PyStrRef, PyTupleRef, PyTypeRef},
         function::{ArgBytesLike, ArgMemoryBuffer, PosArgs},
         match_class,
         protocol::PyIterReturn,
         types::{Constructor, IterNext, Iterable, SelfIter},
-        AsObject, Py, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
 
diff --git a/stdlib/src/random.rs b/stdlib/src/random.rs
index 1dfc4fcc30..685c0ae8b9 100644
--- a/stdlib/src/random.rs
+++ b/stdlib/src/random.rs
@@ -6,79 +6,37 @@ pub(crate) use _random::make_module;
 mod _random {
     use crate::common::lock::PyMutex;
     use crate::vm::{
-        builtins::{PyInt, PyTypeRef},
+        PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
+        builtins::{PyInt, PyTupleRef},
+        convert::ToPyException,
         function::OptionalOption,
-        types::Constructor,
-        PyObjectRef, PyPayload, PyResult, VirtualMachine,
+        types::{Constructor, Initializer},
     };
+    use itertools::Itertools;
     use malachite_bigint::{BigInt, BigUint, Sign};
+    use mt19937::MT19937;
     use num_traits::{Signed, Zero};
-    use rand::{rngs::StdRng, RngCore, SeedableRng};
-
-    #[derive(Debug)]
-    enum PyRng {
-        Std(Box<StdRng>),
-        MT(Box<mt19937::MT19937>),
-    }
-
-    impl Default for PyRng {
-        fn default() -> Self {
-            PyRng::Std(Box::new(StdRng::from_entropy()))
-        }
-    }
-
-    impl RngCore for PyRng {
-        fn next_u32(&mut self) -> u32 {
-            match self {
-                Self::Std(s) => s.next_u32(),
-                Self::MT(m) => m.next_u32(),
-            }
-        }
-        fn next_u64(&mut self) -> u64 {
-            match self {
-                Self::Std(s) => s.next_u64(),
-                Self::MT(m) => m.next_u64(),
-            }
-        }
-        fn fill_bytes(&mut self, dest: &mut [u8]) {
-            match self {
-                Self::Std(s) => s.fill_bytes(dest),
-                Self::MT(m) => m.fill_bytes(dest),
-            }
-        }
-        fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand::Error> {
-            match self {
-                Self::Std(s) => s.try_fill_bytes(dest),
-                Self::MT(m) => m.try_fill_bytes(dest),
-            }
-        }
-    }
+    use rand::{RngCore, SeedableRng};
+    use rustpython_vm::types::DefaultConstructor;
 
     #[pyattr]
     #[pyclass(name = "Random")]
-    #[derive(Debug, PyPayload)]
+    #[derive(Debug, PyPayload, Default)]
     struct PyRandom {
-        rng: PyMutex<PyRng>,
+        rng: PyMutex<MT19937>,
     }
 
-    impl Constructor for PyRandom {
-        type Args = OptionalOption<PyObjectRef>;
+    impl DefaultConstructor for PyRandom {}
 
-        fn py_new(
-            cls: PyTypeRef,
-            // TODO: use x as the seed.
-            _x: Self::Args,
-            vm: &VirtualMachine,
-        ) -> PyResult {
-            PyRandom {
-                rng: PyMutex::default(),
-            }
-            .into_ref_with_type(vm, cls)
-            .map(Into::into)
+    impl Initializer for PyRandom {
+        type Args = OptionalOption;
+
+        fn init(zelf: PyRef<Self>, x: Self::Args, vm: &VirtualMachine) -> PyResult<()> {
+            zelf.seed(x, vm)
         }
     }
 
-    #[pyclass(flags(BASETYPE), with(Constructor))]
+    #[pyclass(flags(BASETYPE), with(Constructor, Initializer))]
     impl PyRandom {
         #[pymethod]
         fn random(&self) -> f64 {
@@ -88,9 +46,8 @@ mod _random {
 
         #[pymethod]
         fn seed(&self, n: OptionalOption<PyObjectRef>, vm: &VirtualMachine) -> PyResult<()> {
-            let new_rng = n
-                .flatten()
-                .map(|n| {
+            *self.rng.lock() = match n.flatten() {
+                Some(n) => {
                     // Fallback to using hash if object isn't Int-like.
                     let (_, mut key) = match n.downcast::<PyInt>() {
                         Ok(n) => n.as_bigint().abs(),
@@ -101,34 +58,24 @@ mod _random {
                         key.reverse();
                     }
                     let key = if key.is_empty() { &[0] } else { key.as_slice() };
-                    Ok(PyRng::MT(Box::new(mt19937::MT19937::new_with_slice_seed(
-                        key,
-                    ))))
-                })
-                .transpose()?
-                .unwrap_or_default();
-
-            *self.rng.lock() = new_rng;
+                    MT19937::new_with_slice_seed(key)
+                }
+                None => MT19937::try_from_os_rng()
+                    .map_err(|e| std::io::Error::from(e).to_pyexception(vm))?,
+            };
             Ok(())
         }
 
         #[pymethod]
         fn getrandbits(&self, k: isize, vm: &VirtualMachine) -> PyResult<BigInt> {
             match k {
-                k if k < 0 => {
-                    Err(vm.new_value_error("number of bits must be non-negative".to_owned()))
-                }
+                ..0 => Err(vm.new_value_error("number of bits must be non-negative".to_owned())),
                 0 => Ok(BigInt::zero()),
-                _ => {
+                mut k => {
                     let mut rng = self.rng.lock();
-                    let mut k = k;
                     let mut gen_u32 = |k| {
                         let r = rng.next_u32();
-                        if k < 32 {
-                            r >> (32 - k)
-                        } else {
-                            r
-                        }
+                        if k < 32 { r >> (32 - k) } else { r }
                     };
 
                     let words = (k - 1) / 32 + 1;
@@ -151,5 +98,40 @@ mod _random {
                 }
             }
         }
+
+        #[pymethod]
+        fn getstate(&self, vm: &VirtualMachine) -> PyTupleRef {
+            let rng = self.rng.lock();
+            vm.new_tuple(
+                rng.get_state()
+                    .iter()
+                    .copied()
+                    .chain([rng.get_index() as u32])
+                    .map(|i| vm.ctx.new_int(i).into())
+                    .collect::<Vec<PyObjectRef>>(),
+            )
+        }
+
+        #[pymethod]
+        fn setstate(&self, state: PyTupleRef, vm: &VirtualMachine) -> PyResult<()> {
+            let state: &[_; mt19937::N + 1] = state
+                .as_slice()
+                .try_into()
+                .map_err(|_| vm.new_value_error("state vector is the wrong size".to_owned()))?;
+            let (index, state) = state.split_last().unwrap();
+            let index: usize = index.try_to_value(vm)?;
+            if index > mt19937::N {
+                return Err(vm.new_value_error("invalid state".to_owned()));
+            }
+            let state: [u32; mt19937::N] = state
+                .iter()
+                .map(|i| i.try_to_value(vm))
+                .process_results(|it| it.collect_array())?
+                .unwrap();
+            let mut rng = self.rng.lock();
+            rng.set_state(&state);
+            rng.set_index(index);
+            Ok(())
+        }
     }
 }
diff --git a/stdlib/src/resource.rs b/stdlib/src/resource.rs
index c1b74f2b67..e103cce779 100644
--- a/stdlib/src/resource.rs
+++ b/stdlib/src/resource.rs
@@ -3,10 +3,10 @@ pub(crate) use resource::make_module;
 #[pymodule]
 mod resource {
     use crate::vm::{
+        PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, VirtualMachine,
         convert::{ToPyException, ToPyObject},
         stdlib::os,
         types::PyStructSequence,
-        PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, VirtualMachine,
     };
     use std::{io, mem};
 
@@ -24,8 +24,8 @@ mod resource {
     // TODO: RLIMIT_OFILE,
     #[pyattr]
     use libc::{
-        RLIMIT_AS, RLIMIT_CORE, RLIMIT_CPU, RLIMIT_DATA, RLIMIT_FSIZE, RLIMIT_MEMLOCK,
-        RLIMIT_NOFILE, RLIMIT_NPROC, RLIMIT_RSS, RLIMIT_STACK, RLIM_INFINITY,
+        RLIM_INFINITY, RLIMIT_AS, RLIMIT_CORE, RLIMIT_CPU, RLIMIT_DATA, RLIMIT_FSIZE,
+        RLIMIT_MEMLOCK, RLIMIT_NOFILE, RLIMIT_NPROC, RLIMIT_RSS, RLIMIT_STACK,
     };
 
     #[cfg(any(target_os = "linux", target_os = "android", target_os = "emscripten"))]
diff --git a/stdlib/src/scproxy.rs b/stdlib/src/scproxy.rs
index 7108f50d8f..9bf29626ab 100644
--- a/stdlib/src/scproxy.rs
+++ b/stdlib/src/scproxy.rs
@@ -5,9 +5,9 @@ mod _scproxy {
     // straight-forward port of Modules/_scproxy.c
 
     use crate::vm::{
+        PyResult, VirtualMachine,
         builtins::{PyDictRef, PyStr},
         convert::ToPyObject,
-        PyResult, VirtualMachine,
     };
     use system_configuration::core_foundation::{
         array::CFArray,
diff --git a/stdlib/src/select.rs b/stdlib/src/select.rs
index af76d86c8a..4003856bb9 100644
--- a/stdlib/src/select.rs
+++ b/stdlib/src/select.rs
@@ -1,6 +1,6 @@
 use crate::vm::{
-    builtins::PyListRef, builtins::PyModule, PyObject, PyObjectRef, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
+    PyObject, PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine, builtins::PyListRef,
+    builtins::PyModule,
 };
 use std::{io, mem};
 
@@ -19,7 +19,7 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 
 #[cfg(unix)]
 mod platform {
-    pub use libc::{fd_set, select, timeval, FD_ISSET, FD_SET, FD_SETSIZE, FD_ZERO};
+    pub use libc::{FD_ISSET, FD_SET, FD_SETSIZE, FD_ZERO, fd_set, select, timeval};
     pub use std::os::unix::io::RawFd;
 
     pub fn check_err(x: i32) -> bool {
@@ -30,34 +30,36 @@ mod platform {
 #[allow(non_snake_case)]
 #[cfg(windows)]
 mod platform {
+    pub use WinSock::{FD_SET as fd_set, FD_SETSIZE, SOCKET as RawFd, TIMEVAL as timeval, select};
     use windows_sys::Win32::Networking::WinSock;
-    pub use WinSock::{select, FD_SET as fd_set, FD_SETSIZE, SOCKET as RawFd, TIMEVAL as timeval};
 
     // based off winsock2.h: https://gist.github.com/piscisaureus/906386#file-winsock2-h-L128-L141
 
     pub unsafe fn FD_SET(fd: RawFd, set: *mut fd_set) {
-        let mut slot = (&raw mut (*set).fd_array).cast::<RawFd>();
-        let fd_count = (*set).fd_count;
-        for _ in 0..fd_count {
-            if *slot == fd {
-                return;
+        unsafe {
+            let mut slot = (&raw mut (*set).fd_array).cast::<RawFd>();
+            let fd_count = (*set).fd_count;
+            for _ in 0..fd_count {
+                if *slot == fd {
+                    return;
+                }
+                slot = slot.add(1);
+            }
+            // slot == &fd_array[fd_count] at this point
+            if fd_count < FD_SETSIZE {
+                *slot = fd as RawFd;
+                (*set).fd_count += 1;
             }
-            slot = slot.add(1);
-        }
-        // slot == &fd_array[fd_count] at this point
-        if fd_count < FD_SETSIZE {
-            *slot = fd as RawFd;
-            (*set).fd_count += 1;
         }
     }
 
     pub unsafe fn FD_ZERO(set: *mut fd_set) {
-        (*set).fd_count = 0;
+        unsafe { (*set).fd_count = 0 };
     }
 
     pub unsafe fn FD_ISSET(fd: RawFd, set: *mut fd_set) -> bool {
         use WinSock::__WSAFDIsSet;
-        __WSAFDIsSet(fd as _, set) != 0
+        unsafe { __WSAFDIsSet(fd as _, set) != 0 }
     }
 
     pub fn check_err(x: i32) -> bool {
@@ -67,7 +69,7 @@ mod platform {
 
 #[cfg(target_os = "wasi")]
 mod platform {
-    pub use libc::{timeval, FD_SETSIZE};
+    pub use libc::{FD_SETSIZE, timeval};
     pub use std::os::wasi::io::RawFd;
 
     pub fn check_err(x: i32) -> bool {
@@ -82,7 +84,7 @@ mod platform {
 
     #[allow(non_snake_case)]
     pub unsafe fn FD_ISSET(fd: RawFd, set: *const fd_set) -> bool {
-        let set = &*set;
+        let set = unsafe { &*set };
         let n = set.__nfds;
         for p in &set.__fds[..n] {
             if *p == fd {
@@ -94,7 +96,7 @@ mod platform {
 
     #[allow(non_snake_case)]
     pub unsafe fn FD_SET(fd: RawFd, set: *mut fd_set) {
-        let set = &mut *set;
+        let set = unsafe { &mut *set };
         let n = set.__nfds;
         for p in &set.__fds[..n] {
             if *p == fd {
@@ -107,11 +109,11 @@ mod platform {
 
     #[allow(non_snake_case)]
     pub unsafe fn FD_ZERO(set: *mut fd_set) {
-        let set = &mut *set;
+        let set = unsafe { &mut *set };
         set.__nfds = 0;
     }
 
-    extern "C" {
+    unsafe extern "C" {
         pub fn select(
             nfds: libc::c_int,
             readfds: *mut fd_set,
@@ -122,8 +124,8 @@ mod platform {
     }
 }
 
-pub use platform::timeval;
 use platform::RawFd;
+pub use platform::timeval;
 
 #[derive(Traverse)]
 struct Selectable {
@@ -216,11 +218,11 @@ fn sec_to_timeval(sec: f64) -> timeval {
 mod decl {
     use super::*;
     use crate::vm::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::PyTypeRef,
         convert::ToPyException,
         function::{Either, OptionalOption},
         stdlib::time,
-        PyObjectRef, PyResult, VirtualMachine,
     };
 
     #[pyattr]
@@ -325,12 +327,12 @@ mod decl {
     pub(super) mod poll {
         use super::*;
         use crate::vm::{
+            AsObject, PyPayload,
             builtins::PyFloat,
             common::lock::PyMutex,
             convert::{IntoPyException, ToPyObject},
             function::OptionalArg,
             stdlib::io::Fildes,
-            AsObject, PyPayload,
         };
         use libc::pollfd;
         use num_traits::{Signed, ToPrimitive};
@@ -492,8 +494,9 @@ mod decl {
     #[cfg(any(target_os = "linux", target_os = "android", target_os = "redox"))]
     #[pyattr]
     use libc::{
-        EPOLLERR, EPOLLEXCLUSIVE, EPOLLHUP, EPOLLIN, EPOLLMSG, EPOLLONESHOT, EPOLLOUT, EPOLLPRI,
-        EPOLLRDBAND, EPOLLRDHUP, EPOLLRDNORM, EPOLLWAKEUP, EPOLLWRBAND, EPOLLWRNORM, EPOLL_CLOEXEC,
+        EPOLL_CLOEXEC, EPOLLERR, EPOLLEXCLUSIVE, EPOLLHUP, EPOLLIN, EPOLLMSG, EPOLLONESHOT,
+        EPOLLOUT, EPOLLPRI, EPOLLRDBAND, EPOLLRDHUP, EPOLLRDNORM, EPOLLWAKEUP, EPOLLWRBAND,
+        EPOLLWRNORM,
     };
     #[cfg(any(target_os = "linux", target_os = "android", target_os = "redox"))]
     #[pyattr]
@@ -503,13 +506,13 @@ mod decl {
     pub(super) mod epoll {
         use super::*;
         use crate::vm::{
+            PyPayload,
             builtins::PyTypeRef,
             common::lock::{PyRwLock, PyRwLockReadGuard},
             convert::{IntoPyException, ToPyObject},
             function::OptionalArg,
             stdlib::io::Fildes,
             types::Constructor,
-            PyPayload,
         };
         use rustix::event::epoll::{self, EventData, EventFlags};
         use std::ops::Deref;
@@ -643,7 +646,7 @@ mod decl {
                     ..-1 => {
                         return Err(vm.new_value_error(format!(
                             "maxevents must be greater than 0, got {maxevents}"
-                        )))
+                        )));
                     }
                     -1 => libc::FD_SETSIZE - 1,
                     _ => maxevents as usize,
diff --git a/stdlib/src/sha1.rs b/stdlib/src/sha1.rs
index 3820e7d96a..04845bb76b 100644
--- a/stdlib/src/sha1.rs
+++ b/stdlib/src/sha1.rs
@@ -2,7 +2,7 @@ pub(crate) use _sha1::make_module;
 
 #[pymodule]
 mod _sha1 {
-    use crate::hashlib::_hashlib::{local_sha1, HashArgs};
+    use crate::hashlib::_hashlib::{HashArgs, local_sha1};
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
     #[pyfunction]
diff --git a/stdlib/src/sha256.rs b/stdlib/src/sha256.rs
index cae0172666..5d031968ae 100644
--- a/stdlib/src/sha256.rs
+++ b/stdlib/src/sha256.rs
@@ -1,4 +1,4 @@
-use crate::vm::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let _ = vm.import("_hashlib", 0);
@@ -7,7 +7,7 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 
 #[pymodule]
 mod _sha256 {
-    use crate::hashlib::_hashlib::{local_sha224, local_sha256, HashArgs};
+    use crate::hashlib::_hashlib::{HashArgs, local_sha224, local_sha256};
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
     #[pyfunction]
diff --git a/stdlib/src/sha3.rs b/stdlib/src/sha3.rs
index f0c1c5ef69..07b61d9aed 100644
--- a/stdlib/src/sha3.rs
+++ b/stdlib/src/sha3.rs
@@ -3,8 +3,8 @@ pub(crate) use _sha3::make_module;
 #[pymodule]
 mod _sha3 {
     use crate::hashlib::_hashlib::{
-        local_sha3_224, local_sha3_256, local_sha3_384, local_sha3_512, local_shake_128,
-        local_shake_256, HashArgs,
+        HashArgs, local_sha3_224, local_sha3_256, local_sha3_384, local_sha3_512, local_shake_128,
+        local_shake_256,
     };
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
diff --git a/stdlib/src/sha512.rs b/stdlib/src/sha512.rs
index 8c510fb730..baf63fdacf 100644
--- a/stdlib/src/sha512.rs
+++ b/stdlib/src/sha512.rs
@@ -1,4 +1,4 @@
-use crate::vm::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let _ = vm.import("_hashlib", 0);
@@ -7,7 +7,7 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 
 #[pymodule]
 mod _sha512 {
-    use crate::hashlib::_hashlib::{local_sha384, local_sha512, HashArgs};
+    use crate::hashlib::_hashlib::{HashArgs, local_sha384, local_sha512};
     use crate::vm::{PyPayload, PyResult, VirtualMachine};
 
     #[pyfunction]
diff --git a/stdlib/src/socket.rs b/stdlib/src/socket.rs
index bf2f5ecd30..a38b4f123c 100644
--- a/stdlib/src/socket.rs
+++ b/stdlib/src/socket.rs
@@ -1,6 +1,6 @@
-use crate::vm::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule};
 #[cfg(feature = "ssl")]
-pub(super) use _socket::{sock_select, timeout_error_msg, PySocket, SelectKind};
+pub(super) use _socket::{PySocket, SelectKind, sock_select, timeout_error_msg};
 
 pub fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     #[cfg(windows)]
@@ -12,13 +12,13 @@ pub fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 mod _socket {
     use crate::common::lock::{PyMappedRwLockReadGuard, PyRwLock, PyRwLockReadGuard};
     use crate::vm::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyListRef, PyStrRef, PyTupleRef, PyTypeRef},
         common::os::ErrorExt,
         convert::{IntoPyException, ToPyObject, TryFromBorrowedObject, TryFromObject},
         function::{ArgBytesLike, ArgMemoryBuffer, Either, FsPath, OptionalArg, OptionalOption},
         types::{Constructor, DefaultConstructor, Initializer, Representable},
         utils::ToCString,
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use num_traits::ToPrimitive;
@@ -40,32 +40,33 @@ mod _socket {
             INADDR_ANY, INADDR_BROADCAST, INADDR_LOOPBACK, INADDR_NONE,
         };
         pub use winapi::um::winsock2::{
-            getprotobyname, getservbyname, getservbyport, getsockopt, setsockopt,
-            SO_EXCLUSIVEADDRUSE,
+            SO_EXCLUSIVEADDRUSE, getprotobyname, getservbyname, getservbyport, getsockopt,
+            setsockopt,
         };
         pub use winapi::um::ws2tcpip::{
             EAI_AGAIN, EAI_BADFLAGS, EAI_FAIL, EAI_FAMILY, EAI_MEMORY, EAI_NODATA, EAI_NONAME,
             EAI_SERVICE, EAI_SOCKTYPE,
         };
         pub use windows_sys::Win32::Networking::WinSock::{
-            AF_DECnet, AF_APPLETALK, AF_IPX, AF_LINK, AI_ADDRCONFIG, AI_ALL, AI_CANONNAME,
-            AI_NUMERICSERV, AI_V4MAPPED, IPPORT_RESERVED, IPPROTO_AH, IPPROTO_DSTOPTS, IPPROTO_EGP,
-            IPPROTO_ESP, IPPROTO_FRAGMENT, IPPROTO_GGP, IPPROTO_HOPOPTS, IPPROTO_ICMP,
-            IPPROTO_ICMPV6, IPPROTO_IDP, IPPROTO_IGMP, IPPROTO_IP, IPPROTO_IP as IPPROTO_IPIP,
-            IPPROTO_IPV4, IPPROTO_IPV6, IPPROTO_ND, IPPROTO_NONE, IPPROTO_PIM, IPPROTO_PUP,
-            IPPROTO_RAW, IPPROTO_ROUTING, IPPROTO_TCP, IPPROTO_UDP, IPV6_CHECKSUM, IPV6_DONTFRAG,
-            IPV6_HOPLIMIT, IPV6_HOPOPTS, IPV6_JOIN_GROUP, IPV6_LEAVE_GROUP, IPV6_MULTICAST_HOPS,
+            AF_APPLETALK, AF_DECnet, AF_IPX, AF_LINK, AI_ADDRCONFIG, AI_ALL, AI_CANONNAME,
+            AI_NUMERICSERV, AI_V4MAPPED, IP_ADD_MEMBERSHIP, IP_DROP_MEMBERSHIP, IP_HDRINCL,
+            IP_MULTICAST_IF, IP_MULTICAST_LOOP, IP_MULTICAST_TTL, IP_OPTIONS, IP_RECVDSTADDR,
+            IP_TOS, IP_TTL, IPPORT_RESERVED, IPPROTO_AH, IPPROTO_DSTOPTS, IPPROTO_EGP, IPPROTO_ESP,
+            IPPROTO_FRAGMENT, IPPROTO_GGP, IPPROTO_HOPOPTS, IPPROTO_ICMP, IPPROTO_ICMPV6,
+            IPPROTO_IDP, IPPROTO_IGMP, IPPROTO_IP, IPPROTO_IP as IPPROTO_IPIP, IPPROTO_IPV4,
+            IPPROTO_IPV6, IPPROTO_ND, IPPROTO_NONE, IPPROTO_PIM, IPPROTO_PUP, IPPROTO_RAW,
+            IPPROTO_ROUTING, IPPROTO_TCP, IPPROTO_UDP, IPV6_CHECKSUM, IPV6_DONTFRAG, IPV6_HOPLIMIT,
+            IPV6_HOPOPTS, IPV6_JOIN_GROUP, IPV6_LEAVE_GROUP, IPV6_MULTICAST_HOPS,
             IPV6_MULTICAST_IF, IPV6_MULTICAST_LOOP, IPV6_PKTINFO, IPV6_RECVRTHDR, IPV6_RECVTCLASS,
-            IPV6_RTHDR, IPV6_TCLASS, IPV6_UNICAST_HOPS, IPV6_V6ONLY, IP_ADD_MEMBERSHIP,
-            IP_DROP_MEMBERSHIP, IP_HDRINCL, IP_MULTICAST_IF, IP_MULTICAST_LOOP, IP_MULTICAST_TTL,
-            IP_OPTIONS, IP_RECVDSTADDR, IP_TOS, IP_TTL, MSG_BCAST, MSG_CTRUNC, MSG_DONTROUTE,
-            MSG_MCAST, MSG_OOB, MSG_PEEK, MSG_TRUNC, MSG_WAITALL, NI_DGRAM, NI_MAXHOST, NI_MAXSERV,
-            NI_NAMEREQD, NI_NOFQDN, NI_NUMERICHOST, NI_NUMERICSERV, RCVALL_IPLEVEL, RCVALL_OFF,
-            RCVALL_ON, RCVALL_SOCKETLEVELONLY, SD_BOTH as SHUT_RDWR, SD_RECEIVE as SHUT_RD,
-            SD_SEND as SHUT_WR, SIO_KEEPALIVE_VALS, SIO_LOOPBACK_FAST_PATH, SIO_RCVALL, SOCK_DGRAM,
-            SOCK_RAW, SOCK_RDM, SOCK_SEQPACKET, SOCK_STREAM, SOL_SOCKET, SOMAXCONN, SO_BROADCAST,
-            SO_ERROR, SO_LINGER, SO_OOBINLINE, SO_REUSEADDR, SO_TYPE, SO_USELOOPBACK, TCP_NODELAY,
-            WSAEBADF, WSAECONNRESET, WSAENOTSOCK, WSAEWOULDBLOCK,
+            IPV6_RTHDR, IPV6_TCLASS, IPV6_UNICAST_HOPS, IPV6_V6ONLY, MSG_BCAST, MSG_CTRUNC,
+            MSG_DONTROUTE, MSG_MCAST, MSG_OOB, MSG_PEEK, MSG_TRUNC, MSG_WAITALL, NI_DGRAM,
+            NI_MAXHOST, NI_MAXSERV, NI_NAMEREQD, NI_NOFQDN, NI_NUMERICHOST, NI_NUMERICSERV,
+            RCVALL_IPLEVEL, RCVALL_OFF, RCVALL_ON, RCVALL_SOCKETLEVELONLY, SD_BOTH as SHUT_RDWR,
+            SD_RECEIVE as SHUT_RD, SD_SEND as SHUT_WR, SIO_KEEPALIVE_VALS, SIO_LOOPBACK_FAST_PATH,
+            SIO_RCVALL, SO_BROADCAST, SO_ERROR, SO_LINGER, SO_OOBINLINE, SO_REUSEADDR, SO_TYPE,
+            SO_USELOOPBACK, SOCK_DGRAM, SOCK_RAW, SOCK_RDM, SOCK_SEQPACKET, SOCK_STREAM,
+            SOL_SOCKET, SOMAXCONN, TCP_NODELAY, WSAEBADF, WSAECONNRESET, WSAENOTSOCK,
+            WSAEWOULDBLOCK,
         };
         pub const IF_NAMESIZE: usize =
             windows_sys::Win32::NetworkManagement::Ndis::IF_MAX_STRING_SIZE as _;
@@ -86,14 +87,14 @@ mod _socket {
         IPPROTO_ICMPV6, IPPROTO_IP, IPPROTO_IPV6, IPPROTO_TCP, IPPROTO_TCP as SOL_TCP, IPPROTO_UDP,
         MSG_CTRUNC, MSG_DONTROUTE, MSG_OOB, MSG_PEEK, MSG_TRUNC, MSG_WAITALL, NI_DGRAM, NI_MAXHOST,
         NI_NAMEREQD, NI_NOFQDN, NI_NUMERICHOST, NI_NUMERICSERV, SHUT_RD, SHUT_RDWR, SHUT_WR,
-        SOCK_DGRAM, SOCK_STREAM, SOL_SOCKET, SO_BROADCAST, SO_ERROR, SO_LINGER, SO_OOBINLINE,
-        SO_REUSEADDR, SO_TYPE, TCP_NODELAY,
+        SO_BROADCAST, SO_ERROR, SO_LINGER, SO_OOBINLINE, SO_REUSEADDR, SO_TYPE, SOCK_DGRAM,
+        SOCK_STREAM, SOL_SOCKET, TCP_NODELAY,
     };
 
     #[cfg(not(target_os = "redox"))]
     #[pyattr]
     use c::{
-        AF_DECnet, AF_APPLETALK, AF_IPX, IPPROTO_AH, IPPROTO_DSTOPTS, IPPROTO_EGP, IPPROTO_ESP,
+        AF_APPLETALK, AF_DECnet, AF_IPX, IPPROTO_AH, IPPROTO_DSTOPTS, IPPROTO_EGP, IPPROTO_ESP,
         IPPROTO_FRAGMENT, IPPROTO_HOPOPTS, IPPROTO_IDP, IPPROTO_IGMP, IPPROTO_IPIP, IPPROTO_NONE,
         IPPROTO_PIM, IPPROTO_PUP, IPPROTO_RAW, IPPROTO_ROUTING,
     };
@@ -126,8 +127,9 @@ mod _socket {
         J1939_IDLE_ADDR, J1939_MAX_UNICAST_ADDR, J1939_NLA_BYTES_ACKED, J1939_NLA_PAD,
         J1939_NO_ADDR, J1939_NO_NAME, J1939_NO_PGN, J1939_PGN_ADDRESS_CLAIMED,
         J1939_PGN_ADDRESS_COMMANDED, J1939_PGN_MAX, J1939_PGN_PDU1_MAX, J1939_PGN_REQUEST,
-        SCM_J1939_DEST_ADDR, SCM_J1939_DEST_NAME, SCM_J1939_ERRQUEUE, SCM_J1939_PRIO, SOL_CAN_BASE,
-        SOL_CAN_RAW, SO_J1939_ERRQUEUE, SO_J1939_FILTER, SO_J1939_PROMISC, SO_J1939_SEND_PRIO,
+        SCM_J1939_DEST_ADDR, SCM_J1939_DEST_NAME, SCM_J1939_ERRQUEUE, SCM_J1939_PRIO,
+        SO_J1939_ERRQUEUE, SO_J1939_FILTER, SO_J1939_PROMISC, SO_J1939_SEND_PRIO, SOL_CAN_BASE,
+        SOL_CAN_RAW,
     };
 
     #[cfg(all(target_os = "linux", target_env = "gnu"))]
@@ -168,11 +170,11 @@ mod _socket {
     #[pyattr]
     use c::{
         ALG_OP_DECRYPT, ALG_OP_ENCRYPT, ALG_SET_AEAD_ASSOCLEN, ALG_SET_AEAD_AUTHSIZE, ALG_SET_IV,
-        ALG_SET_KEY, ALG_SET_OP, IPV6_DSTOPTS, IPV6_NEXTHOP, IPV6_PATHMTU, IPV6_RECVDSTOPTS,
-        IPV6_RECVHOPLIMIT, IPV6_RECVHOPOPTS, IPV6_RECVPATHMTU, IPV6_RTHDRDSTOPTS,
-        IP_DEFAULT_MULTICAST_LOOP, IP_RECVOPTS, IP_RETOPTS, NETLINK_CRYPTO, NETLINK_DNRTMSG,
-        NETLINK_FIREWALL, NETLINK_IP6_FW, NETLINK_NFLOG, NETLINK_ROUTE, NETLINK_USERSOCK,
-        NETLINK_XFRM, SOL_ALG, SO_PASSSEC, SO_PEERSEC,
+        ALG_SET_KEY, ALG_SET_OP, IP_DEFAULT_MULTICAST_LOOP, IP_RECVOPTS, IP_RETOPTS, IPV6_DSTOPTS,
+        IPV6_NEXTHOP, IPV6_PATHMTU, IPV6_RECVDSTOPTS, IPV6_RECVHOPLIMIT, IPV6_RECVHOPOPTS,
+        IPV6_RECVPATHMTU, IPV6_RTHDRDSTOPTS, NETLINK_CRYPTO, NETLINK_DNRTMSG, NETLINK_FIREWALL,
+        NETLINK_IP6_FW, NETLINK_NFLOG, NETLINK_ROUTE, NETLINK_USERSOCK, NETLINK_XFRM, SO_PASSSEC,
+        SO_PEERSEC, SOL_ALG,
     };
 
     #[cfg(any(target_os = "android", target_vendor = "apple"))]
@@ -190,9 +192,9 @@ mod _socket {
     #[cfg(any(unix, target_os = "android", windows))]
     #[pyattr]
     use c::{
-        INADDR_BROADCAST, IPV6_MULTICAST_HOPS, IPV6_MULTICAST_IF, IPV6_MULTICAST_LOOP,
-        IPV6_UNICAST_HOPS, IPV6_V6ONLY, IP_ADD_MEMBERSHIP, IP_DROP_MEMBERSHIP, IP_MULTICAST_IF,
-        IP_MULTICAST_LOOP, IP_MULTICAST_TTL, IP_TTL,
+        INADDR_BROADCAST, IP_ADD_MEMBERSHIP, IP_DROP_MEMBERSHIP, IP_MULTICAST_IF,
+        IP_MULTICAST_LOOP, IP_MULTICAST_TTL, IP_TTL, IPV6_MULTICAST_HOPS, IPV6_MULTICAST_IF,
+        IPV6_MULTICAST_LOOP, IPV6_UNICAST_HOPS, IPV6_V6ONLY,
     };
 
     #[cfg(any(unix, target_os = "android", windows))]
@@ -213,8 +215,8 @@ mod _socket {
         AF_ALG, AF_ASH, AF_ATMPVC, AF_ATMSVC, AF_AX25, AF_BRIDGE, AF_CAN, AF_ECONET, AF_IRDA,
         AF_LLC, AF_NETBEUI, AF_NETLINK, AF_NETROM, AF_PACKET, AF_PPPOX, AF_RDS, AF_SECURITY,
         AF_TIPC, AF_VSOCK, AF_WANPIPE, AF_X25, IP_TRANSPARENT, MSG_CONFIRM, MSG_ERRQUEUE,
-        MSG_FASTOPEN, MSG_MORE, PF_CAN, PF_PACKET, PF_RDS, SCM_CREDENTIALS, SOL_IP, SOL_TIPC,
-        SOL_UDP, SO_BINDTODEVICE, SO_MARK, TCP_CORK, TCP_DEFER_ACCEPT, TCP_LINGER2, TCP_QUICKACK,
+        MSG_FASTOPEN, MSG_MORE, PF_CAN, PF_PACKET, PF_RDS, SCM_CREDENTIALS, SO_BINDTODEVICE,
+        SO_MARK, SOL_IP, SOL_TIPC, SOL_UDP, TCP_CORK, TCP_DEFER_ACCEPT, TCP_LINGER2, TCP_QUICKACK,
         TCP_SYNCNT, TCP_WINDOW_CLAMP,
     };
 
@@ -271,7 +273,7 @@ mod _socket {
 
     #[cfg(any(target_os = "android", target_os = "linux", windows))]
     #[pyattr]
-    use c::{IPV6_HOPOPTS, IPV6_RECVRTHDR, IPV6_RTHDR, IP_OPTIONS};
+    use c::{IP_OPTIONS, IPV6_HOPOPTS, IPV6_RECVRTHDR, IPV6_RTHDR};
 
     #[cfg(any(
         target_os = "dragonfly",
@@ -525,7 +527,7 @@ mod _socket {
     ))]
     #[pyattr]
     use c::{
-        AF_LINK, IPPROTO_GGP, IPV6_JOIN_GROUP, IPV6_LEAVE_GROUP, IP_RECVDSTADDR, SO_USELOOPBACK,
+        AF_LINK, IP_RECVDSTADDR, IPPROTO_GGP, IPV6_JOIN_GROUP, IPV6_LEAVE_GROUP, SO_USELOOPBACK,
     };
 
     #[cfg(any(
@@ -633,7 +635,7 @@ mod _socket {
     #[pyattr]
     use c::{
         EAI_AGAIN, EAI_BADFLAGS, EAI_FAIL, EAI_FAMILY, EAI_MEMORY, EAI_NONAME, EAI_SERVICE,
-        EAI_SOCKTYPE, IPV6_RECVTCLASS, IPV6_TCLASS, IP_HDRINCL, IP_TOS, SOMAXCONN,
+        EAI_SOCKTYPE, IP_HDRINCL, IP_TOS, IPV6_RECVTCLASS, IPV6_TCLASS, SOMAXCONN,
     };
 
     #[cfg(not(any(
@@ -1473,11 +1475,7 @@ mod _socket {
         #[pymethod]
         fn gettimeout(&self) -> Option<f64> {
             let timeout = self.timeout.load();
-            if timeout >= 0.0 {
-                Some(timeout)
-            } else {
-                None
-            }
+            if timeout >= 0.0 { Some(timeout) } else { None }
         }
 
         #[pymethod]
@@ -1601,7 +1599,7 @@ mod _socket {
                 _ => {
                     return Err(vm
                         .new_value_error("`how` must be SHUT_RD, SHUT_WR, or SHUT_RDWR".to_owned())
-                        .into())
+                        .into());
                 }
             };
             Ok(self.sock()?.shutdown(how)?)
@@ -1788,7 +1786,7 @@ mod _socket {
     }
 
     unsafe fn slice_as_uninit<T>(v: &mut [T]) -> &mut [MaybeUninit<T>] {
-        &mut *(v as *mut [T] as *mut [MaybeUninit<T>])
+        unsafe { &mut *(v as *mut [T] as *mut [MaybeUninit<T>]) }
     }
 
     enum IoOrPyException {
@@ -1924,7 +1922,7 @@ mod _socket {
         let host = opts.host.as_ref().map(|s| s.as_str());
         let port = opts.port.as_ref().map(|p| -> std::borrow::Cow<str> {
             match p {
-                Either::A(ref s) => s.as_str().into(),
+                Either::A(s) => s.as_str().into(),
                 Either::B(i) => i.to_string().into(),
             }
         });
@@ -2054,7 +2052,7 @@ mod _socket {
             _ => {
                 return Err(vm
                     .new_type_error("illegal sockaddr argument".to_owned())
-                    .into())
+                    .into());
             }
         }
         let (addr, flowinfo, scopeid) = Address::from_tuple_ipv6(&address, vm)?;
@@ -2259,7 +2257,7 @@ mod _socket {
                 _ => {
                     return Err(vm
                         .new_os_error("address family mismatched".to_owned())
-                        .into())
+                        .into());
                 }
             }
             return Ok(SocketAddr::V4(net::SocketAddrV4::new(
@@ -2312,12 +2310,12 @@ mod _socket {
         #[cfg(unix)]
         {
             use std::os::unix::io::FromRawFd;
-            Socket::from_raw_fd(fileno)
+            unsafe { Socket::from_raw_fd(fileno) }
         }
         #[cfg(windows)]
         {
             use std::os::windows::io::FromRawSocket;
-            Socket::from_raw_socket(fileno)
+            unsafe { Socket::from_raw_socket(fileno) }
         }
     }
     pub(super) fn sock_fileno(sock: &Socket) -> RawSocket {
@@ -2433,11 +2431,7 @@ mod _socket {
     #[pyfunction]
     fn getdefaulttimeout() -> Option<f64> {
         let timeout = DEFAULT_TIMEOUT.load();
-        if timeout >= 0.0 {
-            Some(timeout)
-        } else {
-            None
-        }
+        if timeout >= 0.0 { Some(timeout) } else { None }
     }
 
     #[pyfunction]
diff --git a/stdlib/src/sqlite.rs b/stdlib/src/sqlite.rs
index 6cb3deae7d..5487511e20 100644
--- a/stdlib/src/sqlite.rs
+++ b/stdlib/src/sqlite.rs
@@ -8,7 +8,7 @@
 // spell-checker:ignore cantlock commithook foreignkey notnull primarykey gettemppath autoindex convpath
 // spell-checker:ignore dbmoved vnode nbytes
 
-use rustpython_vm::{builtins::PyModule, AsObject, PyRef, VirtualMachine};
+use rustpython_vm::{AsObject, PyRef, VirtualMachine, builtins::PyModule};
 
 // pub(crate) use _sqlite::make_module;
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
@@ -21,29 +21,29 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 #[pymodule]
 mod _sqlite {
     use libsqlite3_sys::{
-        sqlite3, sqlite3_aggregate_context, sqlite3_backup_finish, sqlite3_backup_init,
-        sqlite3_backup_pagecount, sqlite3_backup_remaining, sqlite3_backup_step, sqlite3_bind_blob,
-        sqlite3_bind_double, sqlite3_bind_int64, sqlite3_bind_null, sqlite3_bind_parameter_count,
-        sqlite3_bind_parameter_name, sqlite3_bind_text, sqlite3_blob, sqlite3_blob_bytes,
-        sqlite3_blob_close, sqlite3_blob_open, sqlite3_blob_read, sqlite3_blob_write,
-        sqlite3_busy_timeout, sqlite3_changes, sqlite3_close_v2, sqlite3_column_blob,
-        sqlite3_column_bytes, sqlite3_column_count, sqlite3_column_decltype, sqlite3_column_double,
-        sqlite3_column_int64, sqlite3_column_name, sqlite3_column_text, sqlite3_column_type,
-        sqlite3_complete, sqlite3_context, sqlite3_context_db_handle, sqlite3_create_collation_v2,
-        sqlite3_create_function_v2, sqlite3_create_window_function, sqlite3_data_count,
-        sqlite3_db_handle, sqlite3_errcode, sqlite3_errmsg, sqlite3_exec, sqlite3_expanded_sql,
-        sqlite3_extended_errcode, sqlite3_finalize, sqlite3_get_autocommit, sqlite3_interrupt,
-        sqlite3_last_insert_rowid, sqlite3_libversion, sqlite3_limit, sqlite3_open_v2,
-        sqlite3_prepare_v2, sqlite3_progress_handler, sqlite3_reset, sqlite3_result_blob,
-        sqlite3_result_double, sqlite3_result_error, sqlite3_result_error_nomem,
-        sqlite3_result_error_toobig, sqlite3_result_int64, sqlite3_result_null,
-        sqlite3_result_text, sqlite3_set_authorizer, sqlite3_sleep, sqlite3_step, sqlite3_stmt,
-        sqlite3_stmt_busy, sqlite3_stmt_readonly, sqlite3_threadsafe, sqlite3_total_changes,
-        sqlite3_trace_v2, sqlite3_user_data, sqlite3_value, sqlite3_value_blob,
-        sqlite3_value_bytes, sqlite3_value_double, sqlite3_value_int64, sqlite3_value_text,
-        sqlite3_value_type, SQLITE_BLOB, SQLITE_DETERMINISTIC, SQLITE_FLOAT, SQLITE_INTEGER,
-        SQLITE_NULL, SQLITE_OPEN_CREATE, SQLITE_OPEN_READWRITE, SQLITE_OPEN_URI, SQLITE_TEXT,
-        SQLITE_TRACE_STMT, SQLITE_TRANSIENT, SQLITE_UTF8,
+        SQLITE_BLOB, SQLITE_DETERMINISTIC, SQLITE_FLOAT, SQLITE_INTEGER, SQLITE_NULL,
+        SQLITE_OPEN_CREATE, SQLITE_OPEN_READWRITE, SQLITE_OPEN_URI, SQLITE_TEXT, SQLITE_TRACE_STMT,
+        SQLITE_TRANSIENT, SQLITE_UTF8, sqlite3, sqlite3_aggregate_context, sqlite3_backup_finish,
+        sqlite3_backup_init, sqlite3_backup_pagecount, sqlite3_backup_remaining,
+        sqlite3_backup_step, sqlite3_bind_blob, sqlite3_bind_double, sqlite3_bind_int64,
+        sqlite3_bind_null, sqlite3_bind_parameter_count, sqlite3_bind_parameter_name,
+        sqlite3_bind_text, sqlite3_blob, sqlite3_blob_bytes, sqlite3_blob_close, sqlite3_blob_open,
+        sqlite3_blob_read, sqlite3_blob_write, sqlite3_busy_timeout, sqlite3_changes,
+        sqlite3_close_v2, sqlite3_column_blob, sqlite3_column_bytes, sqlite3_column_count,
+        sqlite3_column_decltype, sqlite3_column_double, sqlite3_column_int64, sqlite3_column_name,
+        sqlite3_column_text, sqlite3_column_type, sqlite3_complete, sqlite3_context,
+        sqlite3_context_db_handle, sqlite3_create_collation_v2, sqlite3_create_function_v2,
+        sqlite3_create_window_function, sqlite3_data_count, sqlite3_db_handle, sqlite3_errcode,
+        sqlite3_errmsg, sqlite3_exec, sqlite3_expanded_sql, sqlite3_extended_errcode,
+        sqlite3_finalize, sqlite3_get_autocommit, sqlite3_interrupt, sqlite3_last_insert_rowid,
+        sqlite3_libversion, sqlite3_limit, sqlite3_open_v2, sqlite3_prepare_v2,
+        sqlite3_progress_handler, sqlite3_reset, sqlite3_result_blob, sqlite3_result_double,
+        sqlite3_result_error, sqlite3_result_error_nomem, sqlite3_result_error_toobig,
+        sqlite3_result_int64, sqlite3_result_null, sqlite3_result_text, sqlite3_set_authorizer,
+        sqlite3_sleep, sqlite3_step, sqlite3_stmt, sqlite3_stmt_busy, sqlite3_stmt_readonly,
+        sqlite3_threadsafe, sqlite3_total_changes, sqlite3_trace_v2, sqlite3_user_data,
+        sqlite3_value, sqlite3_value_blob, sqlite3_value_bytes, sqlite3_value_double,
+        sqlite3_value_int64, sqlite3_value_text, sqlite3_value_type,
     };
     use malachite_bigint::Sign;
     use rustpython_common::{
@@ -53,13 +53,16 @@ mod _sqlite {
         static_cell,
     };
     use rustpython_vm::{
-        atomic_func,
+        __exports::paste,
+        AsObject, Py, PyAtomicRef, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+        TryFromBorrowedObject, VirtualMachine, atomic_func,
         builtins::{
             PyBaseException, PyBaseExceptionRef, PyByteArray, PyBytes, PyDict, PyDictRef, PyFloat,
             PyInt, PyIntRef, PySlice, PyStr, PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef,
         },
         convert::IntoObject,
         function::{ArgCallable, ArgIterable, FsPath, FuncArgs, OptionalArg, PyComparisonValue},
+        object::{Traverse, TraverseFn},
         protocol::{PyBuffer, PyIterReturn, PyMappingMethods, PySequence, PySequenceMethods},
         sliceable::{SaturatedSliceIter, SliceableSequenceOp},
         types::{
@@ -67,16 +70,12 @@ mod _sqlite {
             PyComparisonOp, SelfIter,
         },
         utils::ToCString,
-        AsObject, Py, PyAtomicRef, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-        TryFromBorrowedObject, VirtualMachine,
-        __exports::paste,
-        object::{Traverse, TraverseFn},
     };
     use std::{
-        ffi::{c_int, c_longlong, c_uint, c_void, CStr},
+        ffi::{CStr, c_int, c_longlong, c_uint, c_void},
         fmt::Debug,
         ops::Deref,
-        ptr::{null, null_mut},
+        ptr::{NonNull, null, null_mut},
         thread::ThreadId,
     };
 
@@ -381,7 +380,7 @@ mod _sqlite {
     }
 
     struct CallbackData {
-        obj: *const PyObject,
+        obj: NonNull<PyObject>,
         vm: *const VirtualMachine,
     }
 
@@ -394,11 +393,11 @@ mod _sqlite {
         }
 
         fn retrieve(&self) -> (&PyObject, &VirtualMachine) {
-            unsafe { (&*self.obj, &*self.vm) }
+            unsafe { (self.obj.as_ref(), &*self.vm) }
         }
 
         unsafe extern "C" fn destructor(data: *mut c_void) {
-            drop(Box::from_raw(data.cast::<Self>()));
+            drop(unsafe { Box::from_raw(data.cast::<Self>()) });
         }
 
         unsafe extern "C" fn func_callback(
@@ -407,8 +406,8 @@ mod _sqlite {
             argv: *mut *mut sqlite3_value,
         ) {
             let context = SqliteContext::from(context);
-            let (func, vm) = (*context.user_data::<Self>()).retrieve();
-            let args = std::slice::from_raw_parts(argv, argc as usize);
+            let (func, vm) = unsafe { (*context.user_data::<Self>()).retrieve() };
+            let args = unsafe { std::slice::from_raw_parts(argv, argc as usize) };
 
             let f = || -> PyResult<()> {
                 let db = context.db_handle();
@@ -434,31 +433,31 @@ mod _sqlite {
             argv: *mut *mut sqlite3_value,
         ) {
             let context = SqliteContext::from(context);
-            let (cls, vm) = (*context.user_data::<Self>()).retrieve();
-            let args = std::slice::from_raw_parts(argv, argc as usize);
+            let (cls, vm) = unsafe { (*context.user_data::<Self>()).retrieve() };
+            let args = unsafe { std::slice::from_raw_parts(argv, argc as usize) };
             let instance = context.aggregate_context::<*const PyObject>();
-            if (*instance).is_null() {
+            if unsafe { (*instance).is_null() } {
                 match cls.call((), vm) {
-                    Ok(obj) => *instance = obj.into_raw(),
+                    Ok(obj) => unsafe { *instance = obj.into_raw().as_ptr() },
                     Err(exc) => {
                         return context.result_exception(
                             vm,
                             exc,
                             "user-defined aggregate's '__init__' method raised error\0",
-                        )
+                        );
                     }
                 }
             }
-            let instance = &**instance;
+            let instance = unsafe { &**instance };
 
             Self::call_method_with_args(context, instance, "step", args, vm);
         }
 
         unsafe extern "C" fn finalize_callback(context: *mut sqlite3_context) {
             let context = SqliteContext::from(context);
-            let (_, vm) = (*context.user_data::<Self>()).retrieve();
+            let (_, vm) = unsafe { (*context.user_data::<Self>()).retrieve() };
             let instance = context.aggregate_context::<*const PyObject>();
-            let Some(instance) = (*instance).as_ref() else {
+            let Some(instance) = (unsafe { (*instance).as_ref() }) else {
                 return;
             };
 
@@ -472,7 +471,7 @@ mod _sqlite {
             b_len: c_int,
             b_ptr: *const c_void,
         ) -> c_int {
-            let (callable, vm) = (*data.cast::<Self>()).retrieve();
+            let (callable, vm) = unsafe { (*data.cast::<Self>()).retrieve() };
 
             let f = || -> PyResult<c_int> {
                 let text1 = ptr_to_string(a_ptr.cast(), a_len, null_mut(), vm)?;
@@ -499,9 +498,9 @@ mod _sqlite {
 
         unsafe extern "C" fn value_callback(context: *mut sqlite3_context) {
             let context = SqliteContext::from(context);
-            let (_, vm) = (*context.user_data::<Self>()).retrieve();
+            let (_, vm) = unsafe { (*context.user_data::<Self>()).retrieve() };
             let instance = context.aggregate_context::<*const PyObject>();
-            let instance = &**instance;
+            let instance = unsafe { &**instance };
 
             Self::callback_result_from_method(context, instance, "value", vm);
         }
@@ -512,10 +511,10 @@ mod _sqlite {
             argv: *mut *mut sqlite3_value,
         ) {
             let context = SqliteContext::from(context);
-            let (_, vm) = (*context.user_data::<Self>()).retrieve();
-            let args = std::slice::from_raw_parts(argv, argc as usize);
+            let (_, vm) = unsafe { (*context.user_data::<Self>()).retrieve() };
+            let args = unsafe { std::slice::from_raw_parts(argv, argc as usize) };
             let instance = context.aggregate_context::<*const PyObject>();
-            let instance = &**instance;
+            let instance = unsafe { &**instance };
 
             Self::call_method_with_args(context, instance, "inverse", args, vm);
         }
@@ -528,7 +527,7 @@ mod _sqlite {
             db_name: *const libc::c_char,
             access: *const libc::c_char,
         ) -> c_int {
-            let (callable, vm) = (*data.cast::<Self>()).retrieve();
+            let (callable, vm) = unsafe { (*data.cast::<Self>()).retrieve() };
             let f = || -> PyResult<c_int> {
                 let arg1 = ptr_to_str(arg1, vm)?;
                 let arg2 = ptr_to_str(arg2, vm)?;
@@ -551,8 +550,8 @@ mod _sqlite {
             stmt: *mut c_void,
             sql: *mut c_void,
         ) -> c_int {
-            let (callable, vm) = (*data.cast::<Self>()).retrieve();
-            let expanded = sqlite3_expanded_sql(stmt.cast());
+            let (callable, vm) = unsafe { (*data.cast::<Self>()).retrieve() };
+            let expanded = unsafe { sqlite3_expanded_sql(stmt.cast()) };
             let f = || -> PyResult<()> {
                 let stmt = ptr_to_str(expanded, vm).or_else(|_| ptr_to_str(sql.cast(), vm))?;
                 callable.call((stmt,), vm)?;
@@ -563,7 +562,7 @@ mod _sqlite {
         }
 
         unsafe extern "C" fn progress_callback(data: *mut c_void) -> c_int {
-            let (callable, vm) = (*data.cast::<Self>()).retrieve();
+            let (callable, vm) = unsafe { (*data.cast::<Self>()).retrieve() };
             if let Ok(val) = callable.call((), vm) {
                 if let Ok(val) = val.is_true(vm) {
                     return val as c_int;
@@ -2082,7 +2081,7 @@ mod _sqlite {
                 _ => {
                     return Err(vm.new_value_error(
                         "'origin' should be os.SEEK_SET, os.SEEK_CUR, or os.SEEK_END".to_owned(),
-                    ))
+                    ));
                 }
             }
 
diff --git a/stdlib/src/ssl.rs b/stdlib/src/ssl.rs
index 03222ff4f5..2b8ffc7d8c 100644
--- a/stdlib/src/ssl.rs
+++ b/stdlib/src/ssl.rs
@@ -1,19 +1,32 @@
-use crate::vm::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::vm::{PyRef, VirtualMachine, builtins::PyModule};
+use openssl_probe::ProbeResult;
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
-    // if openssl is vendored, it doesn't know the locations of system certificates
-    #[cfg(feature = "ssl-vendor")]
-    if let None | Some("0") = option_env!("OPENSSL_NO_VENDOR") {
-        openssl_probe::init_ssl_cert_env_vars();
-    }
-    openssl::init();
+    // if openssl is vendored, it doesn't know the locations
+    // of system certificates - cache the probe result now.
+    #[cfg(openssl_vendored)]
+    LazyLock::force(&PROBE);
     _ssl::make_module(vm)
 }
 
+// define our own copy of ProbeResult so we can handle the vendor case
+// easily, without having to have a bunch of cfgs
+cfg_if::cfg_if! {
+    if #[cfg(openssl_vendored)] {
+        use std::sync::LazyLock;
+        static PROBE: LazyLock<ProbeResult> = LazyLock::new(openssl_probe::probe);
+        fn probe() -> &'static ProbeResult { &PROBE }
+    } else {
+        fn probe() -> &'static ProbeResult {
+            &ProbeResult { cert_file: None, cert_dir: None }
+        }
+    }
+}
+
 #[allow(non_upper_case_globals)]
 #[pymodule(with(ossl101, windows))]
 mod _ssl {
-    use super::bio;
+    use super::{bio, probe};
     use crate::{
         common::{
             ascii,
@@ -23,6 +36,7 @@ mod _ssl {
         },
         socket::{self, PySocket},
         vm::{
+            PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
             builtins::{PyBaseExceptionRef, PyStrRef, PyType, PyTypeRef, PyWeak},
             convert::{ToPyException, ToPyObject},
             exceptions,
@@ -32,7 +46,6 @@ mod _ssl {
             },
             types::Constructor,
             utils::ToCString,
-            PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         },
     };
     use crossbeam_utils::atomic::AtomicCell;
@@ -42,22 +55,21 @@ mod _ssl {
         error::ErrorStack,
         nid::Nid,
         ssl::{self, SslContextBuilder, SslOptions, SslVerifyMode},
-        x509::{self, X509Ref, X509},
+        x509::{self, X509, X509Ref},
     };
     use openssl_sys as sys;
+    use rustpython_vm::ospath::OsPath;
     use std::{
         ffi::CStr,
         fmt,
         io::{Read, Write},
+        path::Path,
         time::Instant,
     };
 
     // Constants
     #[pyattr]
     use sys::{
-        SSL_OP_NO_SSLv2 as OP_NO_SSLv2,
-        SSL_OP_NO_SSLv3 as OP_NO_SSLv3,
-        SSL_OP_NO_TLSv1 as OP_NO_TLSv1,
         // TODO: so many more of these
         SSL_AD_DECODE_ERROR as ALERT_DESCRIPTION_DECODE_ERROR,
         SSL_AD_ILLEGAL_PARAMETER as ALERT_DESCRIPTION_ILLEGAL_PARAMETER,
@@ -77,7 +89,10 @@ mod _ssl {
         // X509_V_FLAG_X509_STRICT as VERIFY_X509_STRICT,
         SSL_ERROR_ZERO_RETURN,
         SSL_OP_CIPHER_SERVER_PREFERENCE as OP_CIPHER_SERVER_PREFERENCE,
+        SSL_OP_NO_SSLv2 as OP_NO_SSLv2,
+        SSL_OP_NO_SSLv3 as OP_NO_SSLv3,
         SSL_OP_NO_TICKET as OP_NO_TICKET,
+        SSL_OP_NO_TLSv1 as OP_NO_TLSv1,
         SSL_OP_SINGLE_DH_USE as OP_SINGLE_DH_USE,
     };
 
@@ -283,7 +298,7 @@ mod _ssl {
         if ptr.is_null() {
             None
         } else {
-            Some(Asn1Object::from_ptr(ptr))
+            Some(unsafe { Asn1Object::from_ptr(ptr) })
         }
     }
 
@@ -354,21 +369,43 @@ mod _ssl {
             .ok_or_else(|| vm.new_value_error(format!("unknown NID {nid}")))
     }
 
-    #[pyfunction]
-    fn get_default_verify_paths() -> (String, String, String, String) {
-        macro_rules! convert {
-            ($f:ident) => {
-                CStr::from_ptr(sys::$f()).to_string_lossy().into_owned()
-            };
-        }
-        unsafe {
-            (
-                convert!(X509_get_default_cert_file_env),
-                convert!(X509_get_default_cert_file),
-                convert!(X509_get_default_cert_dir_env),
-                convert!(X509_get_default_cert_dir),
-            )
+    fn get_cert_file_dir() -> (&'static Path, &'static Path) {
+        let probe = probe();
+        // on windows, these should be utf8 strings
+        fn path_from_bytes(c: &CStr) -> &Path {
+            #[cfg(unix)]
+            {
+                use std::os::unix::ffi::OsStrExt;
+                std::ffi::OsStr::from_bytes(c.to_bytes()).as_ref()
+            }
+            #[cfg(windows)]
+            {
+                c.to_str().unwrap().as_ref()
+            }
         }
+        let cert_file = probe.cert_file.as_deref().unwrap_or_else(|| {
+            path_from_bytes(unsafe { CStr::from_ptr(sys::X509_get_default_cert_file()) })
+        });
+        let cert_dir = probe.cert_dir.as_deref().unwrap_or_else(|| {
+            path_from_bytes(unsafe { CStr::from_ptr(sys::X509_get_default_cert_dir()) })
+        });
+        (cert_file, cert_dir)
+    }
+
+    #[pyfunction]
+    fn get_default_verify_paths(
+        vm: &VirtualMachine,
+    ) -> PyResult<(&'static str, PyObjectRef, &'static str, PyObjectRef)> {
+        let cert_file_env = unsafe { CStr::from_ptr(sys::X509_get_default_cert_file_env()) }
+            .to_str()
+            .unwrap();
+        let cert_dir_env = unsafe { CStr::from_ptr(sys::X509_get_default_cert_dir_env()) }
+            .to_str()
+            .unwrap();
+        let (cert_file, cert_dir) = get_cert_file_dir();
+        let cert_file = OsPath::new_str(cert_file).filename(vm)?;
+        let cert_dir = OsPath::new_str(cert_dir).filename(vm)?;
+        Ok((cert_file_env, cert_file, cert_dir_env, cert_dir))
     }
 
     #[pyfunction(name = "RAND_status")]
@@ -564,7 +601,7 @@ mod _ssl {
                     return Err(vm.new_value_error(
                         "Cannot set verify_mode to CERT_NONE when check_hostname is enabled."
                             .to_owned(),
-                    ))
+                    ));
                 }
                 CertRequirements::None => SslVerifyMode::NONE,
                 CertRequirements::Optional => SslVerifyMode::PEER,
@@ -590,9 +627,18 @@ mod _ssl {
 
         #[pymethod]
         fn set_default_verify_paths(&self, vm: &VirtualMachine) -> PyResult<()> {
-            self.builder()
-                .set_default_verify_paths()
-                .map_err(|e| convert_openssl_error(vm, e))
+            cfg_if::cfg_if! {
+                if #[cfg(openssl_vendored)] {
+                    let (cert_file, cert_dir) = get_cert_file_dir();
+                    self.builder()
+                        .load_verify_locations(Some(cert_file), Some(cert_dir))
+                        .map_err(|e| convert_openssl_error(vm, e))
+                } else {
+                    self.builder()
+                        .set_default_verify_paths()
+                        .map_err(|e| convert_openssl_error(vm, e))
+                }
+            }
         }
 
         #[pymethod]
@@ -612,7 +658,11 @@ mod _ssl {
                     Ok(pbuf.to_vec())
                 })?;
                 ctx.set_alpn_select_callback(move |_, client| {
-                    ssl::select_next_proto(&server, client).ok_or(ssl::AlpnError::NOACK)
+                    let proto =
+                        ssl::select_next_proto(&server, client).ok_or(ssl::AlpnError::NOACK)?;
+                    let pos = memchr::memmem::find(client, proto)
+                        .expect("selected alpn proto should be present in client protos");
+                    Ok(&client[pos..proto.len()])
                 });
                 Ok(())
             }
@@ -635,6 +685,12 @@ mod _ssl {
                     vm.new_type_error("cafile, capath and cadata cannot be all omitted".to_owned())
                 );
             }
+            if let Some(cafile) = &args.cafile {
+                cafile.ensure_no_nul(vm)?
+            }
+            if let Some(capath) = &args.capath {
+                capath.ensure_no_nul(vm)?
+            }
 
             #[cold]
             fn invalid_cadata(vm: &VirtualMachine) -> PyBaseExceptionRef {
@@ -643,6 +699,8 @@ mod _ssl {
                 )
             }
 
+            let mut ctx = self.builder();
+
             // validate cadata type and load cadata
             if let Some(cadata) = args.cadata {
                 let certs = match cadata {
@@ -655,7 +713,6 @@ mod _ssl {
                     Either::B(b) => b.with_ref(x509_stack_from_der),
                 };
                 let certs = certs.map_err(|e| convert_openssl_error(vm, e))?;
-                let mut ctx = self.builder();
                 let store = ctx.cert_store_mut();
                 for cert in certs {
                     store
@@ -665,29 +722,11 @@ mod _ssl {
             }
 
             if args.cafile.is_some() || args.capath.is_some() {
-                let cafile = args.cafile.map(|s| s.to_cstring(vm)).transpose()?;
-                let capath = args.capath.map(|s| s.to_cstring(vm)).transpose()?;
-                let ret = unsafe {
-                    let ctx = self.ctx.write();
-                    sys::SSL_CTX_load_verify_locations(
-                        ctx.as_ptr(),
-                        cafile
-                            .as_ref()
-                            .map_or_else(std::ptr::null, |cs| cs.as_ptr()),
-                        capath
-                            .as_ref()
-                            .map_or_else(std::ptr::null, |cs| cs.as_ptr()),
-                    )
-                };
-                if ret != 1 {
-                    let errno = crate::common::os::last_posix_errno();
-                    let err = if errno != 0 {
-                        crate::vm::stdlib::os::errno_err(vm)
-                    } else {
-                        convert_openssl_error(vm, ErrorStack::get())
-                    };
-                    return Err(err);
-                }
+                ctx.load_verify_locations(
+                    args.cafile.as_ref().map(|s| s.as_str().as_ref()),
+                    args.capath.as_ref().map(|s| s.as_str().as_ref()),
+                )
+                .map_err(|e| convert_openssl_error(vm, e))?;
             }
 
             Ok(())
@@ -967,11 +1006,7 @@ mod _ssl {
         #[pymethod]
         fn version(&self) -> Option<&'static str> {
             let v = self.stream.read().ssl().version_str();
-            if v == "unknown" {
-                None
-            } else {
-                Some(v)
-            }
+            if v == "unknown" { None } else { Some(v) }
         }
 
         #[pymethod]
@@ -1019,7 +1054,7 @@ mod _ssl {
                         return Err(socket::timeout_error_msg(
                             vm,
                             "The handshake operation timed out".to_owned(),
-                        ))
+                        ));
                     }
                     SelectRet::Closed => return Err(socket_closed_error(vm)),
                     SelectRet::Nonblocking => {}
@@ -1045,7 +1080,7 @@ mod _ssl {
                     return Err(socket::timeout_error_msg(
                         vm,
                         "The write operation timed out".to_owned(),
-                    ))
+                    ));
                 }
                 SelectRet::Closed => return Err(socket_closed_error(vm)),
                 _ => {}
@@ -1061,7 +1096,7 @@ mod _ssl {
                         return Err(socket::timeout_error_msg(
                             vm,
                             "The write operation timed out".to_owned(),
-                        ))
+                        ));
                     }
                     SelectRet::Closed => return Err(socket_closed_error(vm)),
                     SelectRet::Nonblocking => {}
@@ -1113,7 +1148,7 @@ mod _ssl {
                         return Err(socket::timeout_error_msg(
                             vm,
                             "The read operation timed out".to_owned(),
-                        ))
+                        ));
                     }
                     SelectRet::Nonblocking => {}
                     _ => {
@@ -1346,13 +1381,13 @@ mod _ssl {
     #[cfg(target_os = "android")]
     mod android {
         use super::convert_openssl_error;
-        use crate::vm::{builtins::PyBaseExceptionRef, VirtualMachine};
+        use crate::vm::{VirtualMachine, builtins::PyBaseExceptionRef};
         use openssl::{
             ssl::SslContextBuilder,
-            x509::{store::X509StoreBuilder, X509},
+            x509::{X509, store::X509StoreBuilder},
         };
         use std::{
-            fs::{read_dir, File},
+            fs::{File, read_dir},
             io::Read,
             path::Path,
         };
@@ -1426,8 +1461,8 @@ mod windows {}
 mod ossl101 {
     #[pyattr]
     use openssl_sys::{
-        SSL_OP_NO_TLSv1_1 as OP_NO_TLSv1_1, SSL_OP_NO_TLSv1_2 as OP_NO_TLSv1_2,
-        SSL_OP_NO_COMPRESSION as OP_NO_COMPRESSION,
+        SSL_OP_NO_COMPRESSION as OP_NO_COMPRESSION, SSL_OP_NO_TLSv1_1 as OP_NO_TLSv1_1,
+        SSL_OP_NO_TLSv1_2 as OP_NO_TLSv1_2,
     };
 }
 
@@ -1445,15 +1480,15 @@ mod windows {
     use crate::{
         common::ascii,
         vm::{
+            PyObjectRef, PyPayload, PyResult, VirtualMachine,
             builtins::{PyFrozenSet, PyStrRef},
             convert::ToPyException,
-            PyObjectRef, PyPayload, PyResult, VirtualMachine,
         },
     };
 
     #[pyfunction]
     fn enum_certificates(store_name: PyStrRef, vm: &VirtualMachine) -> PyResult<Vec<PyObjectRef>> {
-        use schannel::{cert_context::ValidUses, cert_store::CertStore, RawPointer};
+        use schannel::{RawPointer, cert_context::ValidUses, cert_store::CertStore};
         use windows_sys::Win32::Security::Cryptography;
 
         // TODO: check every store for it, not just 2 of them:
diff --git a/stdlib/src/statistics.rs b/stdlib/src/statistics.rs
index 356bfd66f9..72e5d129a0 100644
--- a/stdlib/src/statistics.rs
+++ b/stdlib/src/statistics.rs
@@ -2,7 +2,7 @@ pub(crate) use _statistics::make_module;
 
 #[pymodule]
 mod _statistics {
-    use crate::vm::{function::ArgIntoFloat, PyResult, VirtualMachine};
+    use crate::vm::{PyResult, VirtualMachine, function::ArgIntoFloat};
 
     // See https://github.com/python/cpython/blob/6846d6712a0894f8e1a91716c11dd79f42864216/Modules/_statisticsmodule.c#L28-L120
     #[allow(clippy::excessive_precision)]
diff --git a/stdlib/src/syslog.rs b/stdlib/src/syslog.rs
index 9879f3ffaf..3b36f9ea74 100644
--- a/stdlib/src/syslog.rs
+++ b/stdlib/src/syslog.rs
@@ -6,10 +6,10 @@ pub(crate) use syslog::make_module;
 mod syslog {
     use crate::common::lock::PyRwLock;
     use crate::vm::{
+        PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyStr, PyStrRef},
         function::{OptionalArg, OptionalOption},
         utils::ToCString,
-        PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     use std::{ffi::CStr, os::raw::c_char};
 
@@ -49,7 +49,7 @@ mod syslog {
     impl GlobalIdent {
         fn as_ptr(&self) -> *const c_char {
             match self {
-                GlobalIdent::Explicit(ref cstr) => cstr.as_ptr(),
+                GlobalIdent::Explicit(cstr) => cstr.as_ptr(),
                 GlobalIdent::Implicit => std::ptr::null(),
             }
         }
diff --git a/stdlib/src/termios.rs b/stdlib/src/termios.rs
index 84c12b2b68..5c49d62a3c 100644
--- a/stdlib/src/termios.rs
+++ b/stdlib/src/termios.rs
@@ -3,10 +3,10 @@ pub(crate) use self::termios::make_module;
 #[pymodule]
 mod termios {
     use crate::vm::{
+        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyBytes, PyInt, PyListRef, PyTypeRef},
         common::os::ErrorExt,
         convert::ToPyObject,
-        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     };
     use termios::Termios;
 
@@ -55,9 +55,9 @@ mod termios {
     ))]
     #[pyattr]
     use libc::{
-        FIONCLEX, FIONREAD, TIOCEXCL, TIOCMBIC, TIOCMBIS, TIOCMGET, TIOCMSET, TIOCM_CAR, TIOCM_CD,
-        TIOCM_CTS, TIOCM_DSR, TIOCM_DTR, TIOCM_LE, TIOCM_RI, TIOCM_RNG, TIOCM_RTS, TIOCM_SR,
-        TIOCM_ST, TIOCNXCL, TIOCSCTTY,
+        FIONCLEX, FIONREAD, TIOCEXCL, TIOCM_CAR, TIOCM_CD, TIOCM_CTS, TIOCM_DSR, TIOCM_DTR,
+        TIOCM_LE, TIOCM_RI, TIOCM_RNG, TIOCM_RTS, TIOCM_SR, TIOCM_ST, TIOCMBIC, TIOCMBIS, TIOCMGET,
+        TIOCMSET, TIOCNXCL, TIOCSCTTY,
     };
     #[cfg(any(target_os = "android", target_os = "linux"))]
     #[pyattr]
@@ -100,12 +100,6 @@ mod termios {
     ))]
     #[pyattr]
     use termios::os::target::TCSASOFT;
-    #[cfg(any(target_os = "android", target_os = "linux"))]
-    #[pyattr]
-    use termios::os::target::{
-        B1000000, B1152000, B1500000, B2000000, B2500000, B3000000, B3500000, B4000000, B500000,
-        B576000, CBAUDEX,
-    };
     #[cfg(any(
         target_os = "android",
         target_os = "freebsd",
@@ -116,6 +110,12 @@ mod termios {
     ))]
     #[pyattr]
     use termios::os::target::{B460800, B921600};
+    #[cfg(any(target_os = "android", target_os = "linux"))]
+    #[pyattr]
+    use termios::os::target::{
+        B500000, B576000, B1000000, B1152000, B1500000, B2000000, B2500000, B3000000, B3500000,
+        B4000000, CBAUDEX,
+    };
     #[cfg(any(
         target_os = "android",
         target_os = "illumos",
@@ -154,16 +154,17 @@ mod termios {
     use termios::os::target::{VSWTCH, VSWTCH as VSWTC};
     #[pyattr]
     use termios::{
+        B0, B50, B75, B110, B134, B150, B200, B300, B600, B1200, B1800, B2400, B4800, B9600,
+        B19200, B38400, BRKINT, CLOCAL, CREAD, CS5, CS6, CS7, CS8, CSIZE, CSTOPB, ECHO, ECHOE,
+        ECHOK, ECHONL, HUPCL, ICANON, ICRNL, IEXTEN, IGNBRK, IGNCR, IGNPAR, INLCR, INPCK, ISIG,
+        ISTRIP, IXANY, IXOFF, IXON, NOFLSH, OCRNL, ONLCR, ONLRET, ONOCR, OPOST, PARENB, PARMRK,
+        PARODD, TCIFLUSH, TCIOFF, TCIOFLUSH, TCION, TCOFLUSH, TCOOFF, TCOON, TCSADRAIN, TCSAFLUSH,
+        TCSANOW, TOSTOP, VEOF, VEOL, VERASE, VINTR, VKILL, VMIN, VQUIT, VSTART, VSTOP, VSUSP,
+        VTIME,
         os::target::{
-            B115200, B230400, B57600, CRTSCTS, ECHOCTL, ECHOKE, ECHOPRT, EXTA, EXTB, FLUSHO,
+            B57600, B115200, B230400, CRTSCTS, ECHOCTL, ECHOKE, ECHOPRT, EXTA, EXTB, FLUSHO,
             IMAXBEL, NCCS, PENDIN, VDISCARD, VEOL2, VLNEXT, VREPRINT, VWERASE,
         },
-        B0, B110, B1200, B134, B150, B1800, B19200, B200, B2400, B300, B38400, B4800, B50, B600,
-        B75, B9600, BRKINT, CLOCAL, CREAD, CS5, CS6, CS7, CS8, CSIZE, CSTOPB, ECHO, ECHOE, ECHOK,
-        ECHONL, HUPCL, ICANON, ICRNL, IEXTEN, IGNBRK, IGNCR, IGNPAR, INLCR, INPCK, ISIG, ISTRIP,
-        IXANY, IXOFF, IXON, NOFLSH, OCRNL, ONLCR, ONLRET, ONOCR, OPOST, PARENB, PARMRK, PARODD,
-        TCIFLUSH, TCIOFF, TCIOFLUSH, TCION, TCOFLUSH, TCOOFF, TCOON, TCSADRAIN, TCSAFLUSH, TCSANOW,
-        TOSTOP, VEOF, VEOL, VERASE, VINTR, VKILL, VMIN, VQUIT, VSTART, VSTOP, VSUSP, VTIME,
     };
 
     #[pyfunction]
diff --git a/stdlib/src/unicodedata.rs b/stdlib/src/unicodedata.rs
index 70483073a7..49f3ef6250 100644
--- a/stdlib/src/unicodedata.rs
+++ b/stdlib/src/unicodedata.rs
@@ -5,8 +5,8 @@
 // spell-checker:ignore nfkc unistr unidata
 
 use crate::vm::{
-    builtins::PyModule, builtins::PyStr, convert::TryFromBorrowedObject, PyObject, PyObjectRef,
-    PyPayload, PyRef, PyResult, VirtualMachine,
+    PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine, builtins::PyModule,
+    builtins::PyStr, convert::TryFromBorrowedObject,
 };
 
 pub fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
@@ -61,14 +61,14 @@ impl<'a> TryFromBorrowedObject<'a> for NormalizeForm {
 #[pymodule]
 mod unicodedata {
     use crate::vm::{
-        builtins::PyStrRef, function::OptionalArg, PyObjectRef, PyPayload, PyRef, PyResult,
-        VirtualMachine,
+        PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine, builtins::PyStrRef,
+        function::OptionalArg,
     };
     use itertools::Itertools;
     use ucd::{Codepoint, EastAsianWidth};
     use unic_char_property::EnumeratedCharProperty;
     use unic_normal::StrNormalForm;
-    use unic_ucd_age::{Age, UnicodeVersion, UNICODE_VERSION};
+    use unic_ucd_age::{Age, UNICODE_VERSION, UnicodeVersion};
     use unic_ucd_bidi::BidiClass;
     use unic_ucd_category::GeneralCategory;
 
diff --git a/stdlib/src/uuid.rs b/stdlib/src/uuid.rs
index e5434da0e1..0bd7d0db8a 100644
--- a/stdlib/src/uuid.rs
+++ b/stdlib/src/uuid.rs
@@ -5,33 +5,19 @@ mod _uuid {
     use crate::{builtins::PyNone, vm::VirtualMachine};
     use mac_address::get_mac_address;
     use once_cell::sync::OnceCell;
-    use rand::Rng;
-    use std::time::{Duration, SystemTime};
-    use uuid::{
-        v1::{Context, Timestamp},
-        Uuid,
-    };
+    use uuid::{Context, Uuid, timestamp::Timestamp};
 
     fn get_node_id() -> [u8; 6] {
         match get_mac_address() {
             Ok(Some(_ma)) => get_mac_address().unwrap().unwrap().bytes(),
-            _ => rand::thread_rng().gen::<[u8; 6]>(),
+            _ => rand::random::<[u8; 6]>(),
         }
     }
 
-    pub fn now_unix_duration() -> Duration {
-        use std::time::UNIX_EPOCH;
-
-        let now = SystemTime::now();
-        now.duration_since(UNIX_EPOCH)
-            .expect("SystemTime before UNIX EPOCH!")
-    }
-
     #[pyfunction]
     fn generate_time_safe() -> (Vec<u8>, PyNone) {
         static CONTEXT: Context = Context::new(0);
-        let now = now_unix_duration();
-        let ts = Timestamp::from_unix(&CONTEXT, now.as_secs(), now.subsec_nanos());
+        let ts = Timestamp::now(&CONTEXT);
 
         static NODE_ID: OnceCell<[u8; 6]> = OnceCell::new();
         let unique_node_id = NODE_ID.get_or_init(get_node_id);
diff --git a/stdlib/src/zlib.rs b/stdlib/src/zlib.rs
index 83a7535c33..19ed659bbb 100644
--- a/stdlib/src/zlib.rs
+++ b/stdlib/src/zlib.rs
@@ -5,49 +5,37 @@ pub(crate) use zlib::make_module;
 #[pymodule]
 mod zlib {
     use crate::vm::{
-        builtins::{PyBaseExceptionRef, PyBytes, PyBytesRef, PyIntRef, PyTypeRef},
+        PyObject, PyPayload, PyResult, VirtualMachine,
+        builtins::{PyBaseExceptionRef, PyBytesRef, PyIntRef, PyTypeRef},
         common::lock::PyMutex,
         convert::TryFromBorrowedObject,
         function::{ArgBytesLike, ArgPrimitiveIndex, ArgSize, OptionalArg},
-        PyObject, PyPayload, PyResult, VirtualMachine,
+        types::Constructor,
     };
     use adler32::RollingAdler32 as Adler32;
-    use crossbeam_utils::atomic::AtomicCell;
     use flate2::{
-        write::ZlibEncoder, Compress, Compression, Decompress, FlushCompress, FlushDecompress,
-        Status,
+        Compress, Compression, Decompress, FlushCompress, FlushDecompress, Status,
+        write::ZlibEncoder,
     };
     use std::io::Write;
 
-    #[cfg(not(feature = "zlib"))]
-    mod constants {
-        pub const Z_NO_COMPRESSION: i32 = 0;
-        pub const Z_BEST_COMPRESSION: i32 = 9;
-        pub const Z_BEST_SPEED: i32 = 1;
-        pub const Z_DEFAULT_COMPRESSION: i32 = -1;
-        pub const Z_NO_FLUSH: i32 = 0;
-        pub const Z_PARTIAL_FLUSH: i32 = 1;
-        pub const Z_SYNC_FLUSH: i32 = 2;
-        pub const Z_FULL_FLUSH: i32 = 3;
-        // not sure what the value here means, but it's the only compression method zlibmodule
-        // supports, so it doesn't really matter
-        pub const Z_DEFLATED: i32 = 8;
-    }
-    #[cfg(feature = "zlib")]
-    use libz_sys as constants;
-
     #[pyattr]
-    use constants::{
-        Z_BEST_COMPRESSION, Z_BEST_SPEED, Z_DEFAULT_COMPRESSION, Z_DEFLATED as DEFLATED,
-        Z_FULL_FLUSH, Z_NO_COMPRESSION, Z_NO_FLUSH, Z_PARTIAL_FLUSH, Z_SYNC_FLUSH,
+    use libz_sys::{
+        Z_BEST_COMPRESSION, Z_BEST_SPEED, Z_BLOCK, Z_DEFAULT_COMPRESSION, Z_DEFAULT_STRATEGY,
+        Z_DEFLATED as DEFLATED, Z_FILTERED, Z_FINISH, Z_FIXED, Z_FULL_FLUSH, Z_HUFFMAN_ONLY,
+        Z_NO_COMPRESSION, Z_NO_FLUSH, Z_PARTIAL_FLUSH, Z_RLE, Z_SYNC_FLUSH, Z_TREES,
     };
 
-    #[cfg(feature = "zlib")]
+    // we're statically linking libz-rs, so the compile-time and runtime
+    // versions will always be the same
+    #[pyattr(name = "ZLIB_RUNTIME_VERSION")]
     #[pyattr]
-    use libz_sys::{
-        Z_BLOCK, Z_DEFAULT_STRATEGY, Z_FILTERED, Z_FINISH, Z_FIXED, Z_HUFFMAN_ONLY, Z_RLE, Z_TREES,
+    const ZLIB_VERSION: &str = unsafe {
+        match std::ffi::CStr::from_ptr(libz_sys::zlibVersion()).to_str() {
+            Ok(s) => s,
+            Err(_) => unreachable!(),
+        }
     };
-    use rustpython_vm::types::Constructor;
 
     // copied from zlibmodule.c (commit 530f506ac91338)
     #[pyattr]
@@ -102,15 +90,10 @@ mod zlib {
         } = args;
         let level = level.ok_or_else(|| new_zlib_error("Bad compression level", vm))?;
 
-        let encoded_bytes = if args.wbits.value == MAX_WBITS {
-            let mut encoder = ZlibEncoder::new(Vec::new(), level);
-            data.with_ref(|input_bytes| encoder.write_all(input_bytes).unwrap());
-            encoder.finish().unwrap()
-        } else {
-            let mut inner = CompressInner::new(InitOptions::new(wbits.value, vm)?.compress(level));
-            data.with_ref(|input_bytes| inner.compress(input_bytes, vm))?;
-            inner.flush(vm)?
-        };
+        let compress = InitOptions::new(wbits.value, vm)?.compress(level);
+        let mut encoder = ZlibEncoder::new_with_compress(Vec::new(), compress);
+        data.with_ref(|input_bytes| encoder.write_all(input_bytes).unwrap());
+        let encoded_bytes = encoder.finish().unwrap();
         Ok(vm.ctx.new_bytes(encoded_bytes))
     }
 
@@ -119,11 +102,11 @@ mod zlib {
             header: bool,
             // [De]Compress::new_with_window_bits is only enabled for zlib; miniz_oxide doesn't
             // support wbits (yet?)
-            #[cfg(feature = "zlib")]
             wbits: u8,
         },
-        #[cfg(feature = "zlib")]
-        Gzip { wbits: u8 },
+        Gzip {
+            wbits: u8,
+        },
     }
 
     impl InitOptions {
@@ -131,12 +114,12 @@ mod zlib {
             let header = wbits > 0;
             let wbits = wbits.unsigned_abs();
             match wbits {
-                9..=15 => Ok(InitOptions::Standard {
-                    header,
-                    #[cfg(feature = "zlib")]
-                    wbits,
-                }),
-                #[cfg(feature = "zlib")]
+                // TODO: wbits = 0 should be a valid option:
+                // > windowBits can also be zero to request that inflate use the window size in
+                // > the zlib header of the compressed stream.
+                // but flate2 doesn't expose it
+                // 0 => ...
+                9..=15 => Ok(InitOptions::Standard { header, wbits }),
                 25..=31 => Ok(InitOptions::Gzip { wbits: wbits - 16 }),
                 _ => Err(vm.new_value_error("Invalid initialization option".to_owned())),
             }
@@ -144,51 +127,95 @@ mod zlib {
 
         fn decompress(self) -> Decompress {
             match self {
-                #[cfg(not(feature = "zlib"))]
-                Self::Standard { header } => Decompress::new(header),
-                #[cfg(feature = "zlib")]
                 Self::Standard { header, wbits } => Decompress::new_with_window_bits(header, wbits),
-                #[cfg(feature = "zlib")]
                 Self::Gzip { wbits } => Decompress::new_gzip(wbits),
             }
         }
         fn compress(self, level: Compression) -> Compress {
             match self {
-                #[cfg(not(feature = "zlib"))]
-                Self::Standard { header } => Compress::new(level, header),
-                #[cfg(feature = "zlib")]
                 Self::Standard { header, wbits } => {
                     Compress::new_with_window_bits(level, header, wbits)
                 }
-                #[cfg(feature = "zlib")]
                 Self::Gzip { wbits } => Compress::new_gzip(level, wbits),
             }
         }
     }
 
+    #[derive(Clone)]
+    struct Chunker<'a> {
+        data1: &'a [u8],
+        data2: &'a [u8],
+    }
+    impl<'a> Chunker<'a> {
+        fn new(data: &'a [u8]) -> Self {
+            Self {
+                data1: data,
+                data2: &[],
+            }
+        }
+        fn chain(data1: &'a [u8], data2: &'a [u8]) -> Self {
+            if data1.is_empty() {
+                Self {
+                    data1: data2,
+                    data2: &[],
+                }
+            } else {
+                Self { data1, data2 }
+            }
+        }
+        fn len(&self) -> usize {
+            self.data1.len() + self.data2.len()
+        }
+        fn is_empty(&self) -> bool {
+            self.data1.is_empty()
+        }
+        fn to_vec(&self) -> Vec<u8> {
+            [self.data1, self.data2].concat()
+        }
+        fn chunk(&self) -> &'a [u8] {
+            self.data1.get(..CHUNKSIZE).unwrap_or(self.data1)
+        }
+        fn advance(&mut self, consumed: usize) {
+            self.data1 = &self.data1[consumed..];
+            if self.data1.is_empty() {
+                self.data1 = std::mem::take(&mut self.data2);
+            }
+        }
+    }
+
     fn _decompress(
-        mut data: &[u8],
+        data: &[u8],
+        d: &mut Decompress,
+        bufsize: usize,
+        max_length: Option<usize>,
+        is_flush: bool,
+        zdict: Option<&ArgBytesLike>,
+        vm: &VirtualMachine,
+    ) -> PyResult<(Vec<u8>, bool)> {
+        let mut data = Chunker::new(data);
+        _decompress_chunks(&mut data, d, bufsize, max_length, is_flush, zdict, vm)
+    }
+
+    fn _decompress_chunks(
+        data: &mut Chunker<'_>,
         d: &mut Decompress,
         bufsize: usize,
         max_length: Option<usize>,
         is_flush: bool,
+        zdict: Option<&ArgBytesLike>,
         vm: &VirtualMachine,
     ) -> PyResult<(Vec<u8>, bool)> {
         if data.is_empty() {
             return Ok((Vec::new(), true));
         }
+        let max_length = max_length.unwrap_or(usize::MAX);
         let mut buf = Vec::new();
 
-        loop {
-            let final_chunk = data.len() <= CHUNKSIZE;
-            let chunk = if final_chunk {
-                data
-            } else {
-                &data[..CHUNKSIZE]
-            };
-            // if this is the final chunk, finish it
+        'outer: loop {
+            let chunk = data.chunk();
             let flush = if is_flush {
-                if final_chunk {
+                // if this is the final chunk, finish it
+                if chunk.len() == data.len() {
                     FlushDecompress::Finish
                 } else {
                     FlushDecompress::None
@@ -197,34 +224,43 @@ mod zlib {
                 FlushDecompress::Sync
             };
             loop {
-                let additional = if let Some(max_length) = max_length {
-                    std::cmp::min(bufsize, max_length - buf.capacity())
-                } else {
-                    bufsize
-                };
+                let additional = std::cmp::min(bufsize, max_length - buf.capacity());
                 if additional == 0 {
                     return Ok((buf, false));
                 }
-
                 buf.reserve_exact(additional);
+
                 let prev_in = d.total_in();
-                let status = d
-                    .decompress_vec(chunk, &mut buf, flush)
-                    .map_err(|_| new_zlib_error("invalid input data", vm))?;
+                let res = d.decompress_vec(chunk, &mut buf, flush);
                 let consumed = d.total_in() - prev_in;
-                data = &data[consumed as usize..];
-                let stream_end = status == Status::StreamEnd;
-                if stream_end || data.is_empty() {
-                    // we've reached the end of the stream, we're done
-                    buf.shrink_to_fit();
-                    return Ok((buf, stream_end));
-                } else if !chunk.is_empty() && consumed == 0 {
-                    // we're gonna need a bigger buffer
-                    continue;
-                } else {
-                    // next chunk
-                    break;
-                }
+
+                data.advance(consumed as usize);
+
+                match res {
+                    Ok(status) => {
+                        let stream_end = status == Status::StreamEnd;
+                        if stream_end || data.is_empty() {
+                            // we've reached the end of the stream, we're done
+                            buf.shrink_to_fit();
+                            return Ok((buf, stream_end));
+                        } else if !chunk.is_empty() && consumed == 0 {
+                            // we're gonna need a bigger buffer
+                            continue;
+                        } else {
+                            // next chunk
+                            continue 'outer;
+                        }
+                    }
+                    Err(e) => {
+                        let Some(zdict) = e.needs_dictionary().and(zdict) else {
+                            return Err(new_zlib_error(&e.to_string(), vm));
+                        };
+                        d.set_dictionary(&zdict.borrow_buf())
+                            .map_err(|_| new_zlib_error("failed to set dictionary", vm))?;
+                        // now try the next chunk
+                        continue 'outer;
+                    }
+                };
             }
         }
     }
@@ -249,7 +285,8 @@ mod zlib {
         } = args;
         data.with_ref(|data| {
             let mut d = InitOptions::new(wbits.value, vm)?.decompress();
-            let (buf, stream_end) = _decompress(data, &mut d, bufsize.value, None, false, vm)?;
+            let (buf, stream_end) =
+                _decompress(data, &mut d, bufsize.value, None, false, None, vm)?;
             if !stream_end {
                 return Err(new_zlib_error(
                     "Error -5 while decompressing data: incomplete or truncated stream",
@@ -264,104 +301,117 @@ mod zlib {
     struct DecompressobjArgs {
         #[pyarg(any, default = "ArgPrimitiveIndex { value: MAX_WBITS }")]
         wbits: ArgPrimitiveIndex<i8>,
-        #[cfg(feature = "zlib")]
         #[pyarg(any, optional)]
-        _zdict: OptionalArg<ArgBytesLike>,
+        zdict: OptionalArg<ArgBytesLike>,
     }
 
     #[pyfunction]
     fn decompressobj(args: DecompressobjArgs, vm: &VirtualMachine) -> PyResult<PyDecompress> {
-        #[allow(unused_mut)]
         let mut decompress = InitOptions::new(args.wbits.value, vm)?.decompress();
-        #[cfg(feature = "zlib")]
-        if let OptionalArg::Present(_dict) = args._zdict {
-            // FIXME: always fails
-            // dict.with_ref(|d| decompress.set_dictionary(d));
+        let zdict = args.zdict.into_option();
+        if let Some(dict) = &zdict {
+            if args.wbits.value < 0 {
+                dict.with_ref(|d| decompress.set_dictionary(d))
+                    .map_err(|_| new_zlib_error("failed to set dictionary", vm))?;
+            }
         }
+        let inner = PyDecompressInner {
+            decompress: Some(decompress),
+            eof: false,
+            zdict,
+            unused_data: vm.ctx.empty_bytes.clone(),
+            unconsumed_tail: vm.ctx.empty_bytes.clone(),
+        };
         Ok(PyDecompress {
-            decompress: PyMutex::new(decompress),
-            eof: AtomicCell::new(false),
-            unused_data: PyMutex::new(PyBytes::from(vec![]).into_ref(&vm.ctx)),
-            unconsumed_tail: PyMutex::new(PyBytes::from(vec![]).into_ref(&vm.ctx)),
+            inner: PyMutex::new(inner),
         })
     }
+
+    #[derive(Debug)]
+    struct PyDecompressInner {
+        decompress: Option<Decompress>,
+        zdict: Option<ArgBytesLike>,
+        eof: bool,
+        unused_data: PyBytesRef,
+        unconsumed_tail: PyBytesRef,
+    }
+
     #[pyattr]
     #[pyclass(name = "Decompress")]
     #[derive(Debug, PyPayload)]
     struct PyDecompress {
-        decompress: PyMutex<Decompress>,
-        eof: AtomicCell<bool>,
-        unused_data: PyMutex<PyBytesRef>,
-        unconsumed_tail: PyMutex<PyBytesRef>,
+        inner: PyMutex<PyDecompressInner>,
     }
+
     #[pyclass]
     impl PyDecompress {
         #[pygetset]
         fn eof(&self) -> bool {
-            self.eof.load()
+            self.inner.lock().eof
         }
         #[pygetset]
         fn unused_data(&self) -> PyBytesRef {
-            self.unused_data.lock().clone()
+            self.inner.lock().unused_data.clone()
         }
         #[pygetset]
         fn unconsumed_tail(&self) -> PyBytesRef {
-            self.unconsumed_tail.lock().clone()
+            self.inner.lock().unconsumed_tail.clone()
         }
 
-        fn save_unused_input(
-            &self,
-            d: &Decompress,
+        fn decompress_inner(
+            inner: &mut PyDecompressInner,
             data: &[u8],
-            stream_end: bool,
-            orig_in: u64,
+            bufsize: usize,
+            max_length: Option<usize>,
+            is_flush: bool,
             vm: &VirtualMachine,
-        ) {
-            let leftover = &data[(d.total_in() - orig_in) as usize..];
-
-            if stream_end && !leftover.is_empty() {
-                let mut unused_data = self.unused_data.lock();
-                let unused: Vec<_> = unused_data
-                    .as_bytes()
-                    .iter()
-                    .chain(leftover)
-                    .copied()
-                    .collect();
-                *unused_data = vm.ctx.new_pyref(unused);
+        ) -> PyResult<(PyResult<Vec<u8>>, bool)> {
+            let Some(d) = &mut inner.decompress else {
+                return Err(new_zlib_error(USE_AFTER_FINISH_ERR, vm));
+            };
+
+            let zdict = if is_flush { None } else { inner.zdict.as_ref() };
+
+            let prev_in = d.total_in();
+            let (ret, stream_end) =
+                match _decompress(data, d, bufsize, max_length, is_flush, zdict, vm) {
+                    Ok((buf, stream_end)) => (Ok(buf), stream_end),
+                    Err(err) => (Err(err), false),
+                };
+            let consumed = (d.total_in() - prev_in) as usize;
+
+            // save unused input
+            let unconsumed = &data[consumed..];
+            if !unconsumed.is_empty() {
+                if stream_end {
+                    let unused = [inner.unused_data.as_bytes(), unconsumed].concat();
+                    inner.unused_data = vm.ctx.new_pyref(unused);
+                } else {
+                    inner.unconsumed_tail = vm.ctx.new_bytes(unconsumed.to_vec());
+                }
+            } else if !inner.unconsumed_tail.is_empty() {
+                inner.unconsumed_tail = vm.ctx.empty_bytes.clone();
             }
+
+            Ok((ret, stream_end))
         }
 
         #[pymethod]
         fn decompress(&self, args: DecompressArgs, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            let max_length = args.max_length.value;
+            let max_length: usize = args
+                .max_length
+                .map_or(0, |x| x.value)
+                .try_into()
+                .map_err(|_| vm.new_value_error("must be non-negative".to_owned()))?;
             let max_length = (max_length != 0).then_some(max_length);
-            let data = args.data.borrow_buf();
-            let data = &*data;
+            let data = &*args.data.borrow_buf();
 
-            let mut d = self.decompress.lock();
-            let orig_in = d.total_in();
+            let inner = &mut *self.inner.lock();
 
             let (ret, stream_end) =
-                match _decompress(data, &mut d, DEF_BUF_SIZE, max_length, false, vm) {
-                    Ok((buf, true)) => {
-                        self.eof.store(true);
-                        (Ok(buf), true)
-                    }
-                    Ok((buf, false)) => (Ok(buf), false),
-                    Err(err) => (Err(err), false),
-                };
-            self.save_unused_input(&d, data, stream_end, orig_in, vm);
-
-            let leftover = if stream_end {
-                b""
-            } else {
-                &data[(d.total_in() - orig_in) as usize..]
-            };
+                Self::decompress_inner(inner, data, DEF_BUF_SIZE, max_length, false, vm)?;
 
-            let mut unconsumed_tail = self.unconsumed_tail.lock();
-            if !leftover.is_empty() || !unconsumed_tail.is_empty() {
-                *unconsumed_tail = PyBytes::from(leftover.to_owned()).into_ref(&vm.ctx);
-            }
+            inner.eof |= stream_end;
 
             ret
         }
@@ -369,36 +419,22 @@ mod zlib {
         #[pymethod]
         fn flush(&self, length: OptionalArg<ArgSize>, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
             let length = match length {
-                OptionalArg::Present(l) => {
-                    let l: isize = l.into();
-                    if l <= 0 {
-                        return Err(
-                            vm.new_value_error("length must be greater than zero".to_owned())
-                        );
-                    } else {
-                        l as usize
-                    }
+                OptionalArg::Present(ArgSize { value }) if value <= 0 => {
+                    return Err(vm.new_value_error("length must be greater than zero".to_owned()));
                 }
+                OptionalArg::Present(ArgSize { value }) => value as usize,
                 OptionalArg::Missing => DEF_BUF_SIZE,
             };
 
-            let mut data = self.unconsumed_tail.lock();
-            let mut d = self.decompress.lock();
+            let inner = &mut *self.inner.lock();
+            let data = std::mem::replace(&mut inner.unconsumed_tail, vm.ctx.empty_bytes.clone());
 
-            let orig_in = d.total_in();
+            let (ret, _) = Self::decompress_inner(inner, &data, length, None, true, vm)?;
 
-            let (ret, stream_end) = match _decompress(&data, &mut d, length, None, true, vm) {
-                Ok((buf, stream_end)) => (Ok(buf), stream_end),
-                Err(err) => (Err(err), false),
-            };
-            self.save_unused_input(&d, &data, stream_end, orig_in, vm);
-
-            *data = PyBytes::from(Vec::new()).into_ref(&vm.ctx);
+            if inner.eof {
+                inner.decompress = None;
+            }
 
-            // TODO: drop the inner decompressor, somehow
-            // if stream_end {
-            //
-            // }
             ret
         }
     }
@@ -407,11 +443,8 @@ mod zlib {
     struct DecompressArgs {
         #[pyarg(positional)]
         data: ArgBytesLike,
-        #[pyarg(
-            any,
-            default = "rustpython_vm::function::ArgPrimitiveIndex { value: 0 }"
-        )]
-        max_length: ArgPrimitiveIndex<usize>,
+        #[pyarg(any, optional)]
+        max_length: OptionalArg<ArgSize>,
     }
 
     #[derive(FromArgs)]
@@ -421,15 +454,13 @@ mod zlib {
         level: Level,
         // only DEFLATED is valid right now, it's w/e
         #[pyarg(any, default = "DEFLATED")]
-        _method: i32,
+        method: i32,
         #[pyarg(any, default = "ArgPrimitiveIndex { value: MAX_WBITS }")]
         wbits: ArgPrimitiveIndex<i8>,
-        #[pyarg(any, name = "_memLevel", default = "DEF_MEM_LEVEL")]
-        _mem_level: u8,
-        #[cfg(feature = "zlib")]
+        #[pyarg(any, name = "memLevel", default = "DEF_MEM_LEVEL")]
+        mem_level: u8,
         #[pyarg(any, default = "Z_DEFAULT_STRATEGY")]
-        _strategy: i32,
-        #[cfg(feature = "zlib")]
+        strategy: i32,
         #[pyarg(any, optional)]
         zdict: Option<ArgBytesLike>,
     }
@@ -439,7 +470,6 @@ mod zlib {
         let CompressobjArgs {
             level,
             wbits,
-            #[cfg(feature = "zlib")]
             zdict,
             ..
         } = args;
@@ -447,7 +477,6 @@ mod zlib {
             level.ok_or_else(|| vm.new_value_error("invalid initialization option".to_owned()))?;
         #[allow(unused_mut)]
         let mut compress = InitOptions::new(wbits.value, vm)?.compress(level);
-        #[cfg(feature = "zlib")]
         if let Some(zdict) = zdict {
             zdict.with_ref(|zdict| compress.set_dictionary(zdict).unwrap());
         }
@@ -458,8 +487,7 @@ mod zlib {
 
     #[derive(Debug)]
     struct CompressInner {
-        compress: Compress,
-        unconsumed: Vec<u8>,
+        compress: Option<Compress>,
     }
 
     #[pyattr]
@@ -477,10 +505,17 @@ mod zlib {
             data.with_ref(|b| inner.compress(b, vm))
         }
 
-        // TODO: mode argument isn't used
         #[pymethod]
-        fn flush(&self, _mode: OptionalArg<i32>, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            self.inner.lock().flush(vm)
+        fn flush(&self, mode: OptionalArg<i32>, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
+            let mode = match mode.unwrap_or(Z_FINISH) {
+                Z_NO_FLUSH => return Ok(vec![]),
+                Z_PARTIAL_FLUSH => FlushCompress::Partial,
+                Z_SYNC_FLUSH => FlushCompress::Sync,
+                Z_FULL_FLUSH => FlushCompress::Full,
+                Z_FINISH => FlushCompress::Finish,
+                _ => return Err(new_zlib_error("invalid mode", vm)),
+            };
+            self.inner.lock().flush(mode, vm)
         }
 
         // TODO: This is an optional feature of Compress
@@ -497,59 +532,55 @@ mod zlib {
     impl CompressInner {
         fn new(compress: Compress) -> Self {
             Self {
-                compress,
-                unconsumed: Vec::new(),
+                compress: Some(compress),
             }
         }
+
+        fn get_compress(&mut self, vm: &VirtualMachine) -> PyResult<&mut Compress> {
+            self.compress
+                .as_mut()
+                .ok_or_else(|| new_zlib_error(USE_AFTER_FINISH_ERR, vm))
+        }
+
         fn compress(&mut self, data: &[u8], vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            let orig_in = self.compress.total_in() as usize;
-            let mut cur_in = 0;
-            let unconsumed = std::mem::take(&mut self.unconsumed);
+            let c = self.get_compress(vm)?;
             let mut buf = Vec::new();
 
-            'outer: for chunk in unconsumed.chunks(CHUNKSIZE).chain(data.chunks(CHUNKSIZE)) {
-                while cur_in < chunk.len() {
+            for mut chunk in data.chunks(CHUNKSIZE) {
+                while !chunk.is_empty() {
                     buf.reserve(DEF_BUF_SIZE);
-                    let status = self
-                        .compress
-                        .compress_vec(&chunk[cur_in..], &mut buf, FlushCompress::None)
-                        .map_err(|_| {
-                            self.unconsumed.extend_from_slice(&data[cur_in..]);
-                            new_zlib_error("error while compressing", vm)
-                        })?;
-                    cur_in = (self.compress.total_in() as usize) - orig_in;
-                    match status {
-                        Status::Ok => continue,
-                        Status::StreamEnd => break 'outer,
-                        _ => break,
-                    }
+                    let prev_in = c.total_in();
+                    c.compress_vec(chunk, &mut buf, FlushCompress::None)
+                        .map_err(|_| new_zlib_error("error while compressing", vm))?;
+                    let consumed = c.total_in() - prev_in;
+                    chunk = &chunk[consumed as usize..];
                 }
             }
-            self.unconsumed.extend_from_slice(&data[cur_in..]);
 
             buf.shrink_to_fit();
             Ok(buf)
         }
 
-        // TODO: flush mode (FlushDecompress) parameter
-        fn flush(&mut self, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            let data = std::mem::take(&mut self.unconsumed);
-            let mut data_it = data.chunks(CHUNKSIZE);
+        fn flush(&mut self, mode: FlushCompress, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
+            let c = self.get_compress(vm)?;
             let mut buf = Vec::new();
 
-            loop {
-                let chunk = data_it.next().unwrap_or(&[]);
+            let status = loop {
                 if buf.len() == buf.capacity() {
                     buf.reserve(DEF_BUF_SIZE);
                 }
-                let status = self
-                    .compress
-                    .compress_vec(chunk, &mut buf, FlushCompress::Finish)
+                let status = c
+                    .compress_vec(&[], &mut buf, mode)
                     .map_err(|_| new_zlib_error("error while compressing", vm))?;
-                match status {
-                    Status::StreamEnd => break,
-                    _ => continue,
+                if buf.len() != buf.capacity() {
+                    break status;
                 }
+            };
+
+            match status {
+                Status::Ok | Status::BufError => {}
+                Status::StreamEnd if mode == FlushCompress::Finish => self.compress = None,
+                Status::StreamEnd => return Err(new_zlib_error("unexpected eof", vm)),
             }
 
             buf.shrink_to_fit();
@@ -561,6 +592,8 @@ mod zlib {
         vm.new_exception_msg(vm.class("zlib", "error"), message.to_owned())
     }
 
+    const USE_AFTER_FINISH_ERR: &str = "Error -2: inconsistent stream state";
+
     struct Level(Option<flate2::Compression>);
 
     impl Level {
@@ -592,130 +625,116 @@ mod zlib {
     #[pyattr]
     #[pyclass(name = "_ZlibDecompressor")]
     #[derive(Debug, PyPayload)]
-    pub struct ZlibDecompressor {
-        decompress: PyMutex<Decompress>,
-        unused_data: PyMutex<PyBytesRef>,
-        unconsumed_tail: PyMutex<PyBytesRef>,
+    struct ZlibDecompressor {
+        inner: PyMutex<ZlibDecompressorInner>,
+    }
+
+    #[derive(Debug)]
+    struct ZlibDecompressorInner {
+        decompress: Decompress,
+        unused_data: PyBytesRef,
+        input_buffer: Vec<u8>,
+        zdict: Option<ArgBytesLike>,
+        eof: bool,
+        needs_input: bool,
     }
 
     impl Constructor for ZlibDecompressor {
-        type Args = ();
-
-        fn py_new(cls: PyTypeRef, _args: Self::Args, vm: &VirtualMachine) -> PyResult {
-            let decompress = Decompress::new(true);
-            let zlib_decompressor = Self {
-                decompress: PyMutex::new(decompress),
-                unused_data: PyMutex::new(PyBytes::from(vec![]).into_ref(&vm.ctx)),
-                unconsumed_tail: PyMutex::new(PyBytes::from(vec![]).into_ref(&vm.ctx)),
+        type Args = DecompressobjArgs;
+
+        fn py_new(cls: PyTypeRef, args: Self::Args, vm: &VirtualMachine) -> PyResult {
+            let mut decompress = InitOptions::new(args.wbits.value, vm)?.decompress();
+            let zdict = args.zdict.into_option();
+            if let Some(dict) = &zdict {
+                if args.wbits.value < 0 {
+                    dict.with_ref(|d| decompress.set_dictionary(d))
+                        .map_err(|_| new_zlib_error("failed to set dictionary", vm))?;
+                }
+            }
+            let inner = ZlibDecompressorInner {
+                decompress,
+                unused_data: vm.ctx.empty_bytes.clone(),
+                input_buffer: Vec::new(),
+                zdict,
+                eof: false,
+                needs_input: true,
             };
-            zlib_decompressor
-                .into_ref_with_type(vm, cls)
-                .map(Into::into)
+            Self {
+                inner: PyMutex::new(inner),
+            }
+            .into_ref_with_type(vm, cls)
+            .map(Into::into)
         }
     }
 
     #[pyclass(with(Constructor))]
     impl ZlibDecompressor {
         #[pygetset]
-        fn unused_data(&self) -> PyBytesRef {
-            self.unused_data.lock().clone()
+        fn eof(&self) -> bool {
+            self.inner.lock().eof
         }
 
         #[pygetset]
-        fn unconsumed_tail(&self) -> PyBytesRef {
-            self.unconsumed_tail.lock().clone()
+        fn unused_data(&self) -> PyBytesRef {
+            self.inner.lock().unused_data.clone()
         }
 
-        fn save_unused_input(
-            &self,
-            d: &Decompress,
-            data: &[u8],
-            stream_end: bool,
-            orig_in: u64,
-            vm: &VirtualMachine,
-        ) {
-            let leftover = &data[(d.total_in() - orig_in) as usize..];
-
-            if stream_end && !leftover.is_empty() {
-                let mut unused_data = self.unused_data.lock();
-                let unused: Vec<_> = unused_data
-                    .as_bytes()
-                    .iter()
-                    .chain(leftover)
-                    .copied()
-                    .collect();
-                *unused_data = vm.ctx.new_pyref(unused);
-            }
+        #[pygetset]
+        fn needs_input(&self) -> bool {
+            self.inner.lock().needs_input
         }
 
         #[pymethod]
-        fn decompress(&self, args: PyBytesRef, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            // let max_length = args.max_length.value;
-            // let max_length = (max_length != 0).then_some(max_length);
-            let max_length = None;
-            let data = args.as_bytes();
-
-            let mut d = self.decompress.lock();
-            let orig_in = d.total_in();
-
-            let (ret, stream_end) =
-                match _decompress(data, &mut d, DEF_BUF_SIZE, max_length, false, vm) {
-                    Ok((buf, true)) => {
-                        // Eof is true
-                        (Ok(buf), true)
-                    }
-                    Ok((buf, false)) => (Ok(buf), false),
-                    Err(err) => (Err(err), false),
-                };
-            self.save_unused_input(&d, data, stream_end, orig_in, vm);
+        fn decompress(&self, args: DecompressArgs, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
+            let max_length = args
+                .max_length
+                .into_option()
+                .and_then(|ArgSize { value }| usize::try_from(value).ok());
+            let data = &*args.data.borrow_buf();
 
-            let leftover = if stream_end {
-                b""
-            } else {
-                &data[(d.total_in() - orig_in) as usize..]
-            };
+            let inner = &mut *self.inner.lock();
 
-            let mut unconsumed_tail = self.unconsumed_tail.lock();
-            if !leftover.is_empty() || !unconsumed_tail.is_empty() {
-                *unconsumed_tail = PyBytes::from(leftover.to_owned()).into_ref(&vm.ctx);
+            if inner.eof {
+                return Err(vm.new_eof_error("End of stream already reached".to_owned()));
             }
 
-            ret
-        }
+            let input_buffer = &mut inner.input_buffer;
+            let d = &mut inner.decompress;
 
-        #[pymethod]
-        fn flush(&self, length: OptionalArg<ArgSize>, vm: &VirtualMachine) -> PyResult<Vec<u8>> {
-            let length = match length {
-                OptionalArg::Present(l) => {
-                    let l: isize = l.into();
-                    if l <= 0 {
-                        return Err(
-                            vm.new_value_error("length must be greater than zero".to_owned())
-                        );
-                    } else {
-                        l as usize
-                    }
-                }
-                OptionalArg::Missing => DEF_BUF_SIZE,
-            };
+            let mut chunks = Chunker::chain(input_buffer, data);
 
-            let mut data = self.unconsumed_tail.lock();
-            let mut d = self.decompress.lock();
+            let zdict = inner.zdict.as_ref();
+            let bufsize = DEF_BUF_SIZE;
 
-            let orig_in = d.total_in();
+            let prev_len = chunks.len();
+            let (ret, stream_end) =
+                match _decompress_chunks(&mut chunks, d, bufsize, max_length, false, zdict, vm) {
+                    Ok((buf, stream_end)) => (Ok(buf), stream_end),
+                    Err(err) => (Err(err), false),
+                };
+            let consumed = prev_len - chunks.len();
 
-            let (ret, stream_end) = match _decompress(&data, &mut d, length, None, true, vm) {
-                Ok((buf, stream_end)) => (Ok(buf), stream_end),
-                Err(err) => (Err(err), false),
-            };
-            self.save_unused_input(&d, &data, stream_end, orig_in, vm);
+            inner.eof |= stream_end;
 
-            *data = PyBytes::from(Vec::new()).into_ref(&vm.ctx);
+            if inner.eof {
+                inner.needs_input = false;
+                if !chunks.is_empty() {
+                    inner.unused_data = vm.ctx.new_bytes(chunks.to_vec());
+                }
+            } else if chunks.is_empty() {
+                input_buffer.clear();
+                inner.needs_input = true;
+            } else {
+                inner.needs_input = false;
+                if let Some(n_consumed_from_data) = consumed.checked_sub(input_buffer.len()) {
+                    input_buffer.clear();
+                    input_buffer.extend_from_slice(&data[n_consumed_from_data..]);
+                } else {
+                    input_buffer.drain(..consumed);
+                    input_buffer.extend_from_slice(data);
+                }
+            }
 
-            // TODO: drop the inner decompressor, somehow
-            // if stream_end {
-            //
-            // }
             ret
         }
 
diff --git a/vm/Cargo.toml b/vm/Cargo.toml
index 6eaca281f8..acc645bb74 100644
--- a/vm/Cargo.toml
+++ b/vm/Cargo.toml
@@ -23,7 +23,7 @@ ast = ["rustpython-ast"]
 codegen = ["rustpython-codegen", "ast"]
 parser = ["rustpython-parser", "ast"]
 serde = ["dep:serde"]
-wasmbind = ["chrono/wasmbind", "getrandom/js", "wasm-bindgen"]
+wasmbind = ["chrono/wasmbind", "getrandom/wasm_js", "wasm-bindgen"]
 
 [dependencies]
 rustpython-compiler = { workspace = true, optional = true }
@@ -99,6 +99,9 @@ uname = "0.1.1"
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 rustyline = { workspace = true }
 which = "6"
+errno = "0.3"
+libloading = "0.8"
+widestring = { workspace = true }
 
 [target.'cfg(any(not(target_arch = "wasm32"), target_os = "wasi"))'.dependencies]
 num_cpus = "1.13.1"
@@ -106,8 +109,7 @@ num_cpus = "1.13.1"
 [target.'cfg(windows)'.dependencies]
 junction = { workspace = true }
 schannel = { workspace = true }
-widestring = { workspace = true }
-winreg = "0.52"
+winreg = "0.55"
 
 [target.'cfg(windows)'.dependencies.windows]
 version = "0.52.0"
@@ -115,6 +117,7 @@ features = [
   "Win32_Foundation",
   "Win32_System_LibraryLoader",
   "Win32_System_Threading",
+  "Win32_System_Time",
   "Win32_UI_Shell",
 ]
 
@@ -122,6 +125,7 @@ features = [
 workspace = true
 features = [
   "Win32_Foundation",
+  "Win32_Globalization",
   "Win32_Networking_WinSock",
   "Win32_Security",
   "Win32_Storage_FileSystem",
@@ -143,7 +147,7 @@ features = [
 
 [target.'cfg(all(target_arch = "wasm32", target_os = "unknown"))'.dependencies]
 wasm-bindgen = { workspace = true, optional = true }
-getrandom = { workspace = true, features = ["custom"] }
+getrandom = { workspace = true }
 
 [build-dependencies]
 glob = { workspace = true }
diff --git a/vm/src/anystr.rs b/vm/src/anystr.rs
index f5bfab1c57..0fd1d8f2f6 100644
--- a/vm/src/anystr.rs
+++ b/vm/src/anystr.rs
@@ -1,9 +1,9 @@
 use crate::{
+    Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyIntRef, PyTuple},
     cformat::cformat_string,
     convert::TryFromBorrowedObject,
     function::OptionalOption,
-    Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 use num_traits::{cast::ToPrimitive, sign::Signed};
 
@@ -386,11 +386,7 @@ pub trait AnyStr {
                 b'\n' => (keep, 1),
                 b'\r' => {
                     let is_rn = enumerated.next_if(|(_, ch)| **ch == b'\n').is_some();
-                    if is_rn {
-                        (keep + keep, 2)
-                    } else {
-                        (keep, 1)
-                    }
+                    if is_rn { (keep + keep, 2) } else { (keep, 1) }
                 }
                 _ => continue,
             };
diff --git a/vm/src/buffer.rs b/vm/src/buffer.rs
index bebc7b13a9..3b76002d04 100644
--- a/vm/src/buffer.rs
+++ b/vm/src/buffer.rs
@@ -1,9 +1,9 @@
 use crate::{
+    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyBytesRef, PyTuple, PyTupleRef, PyTypeRef},
     common::{static_cell, str::wchar_t},
     convert::ToPyObject,
     function::{ArgBytesLike, ArgIntoBool, ArgIntoFloat},
-    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 use half::f16;
 use itertools::Itertools;
@@ -99,8 +99,8 @@ impl fmt::Debug for FormatType {
 
 impl FormatType {
     fn info(self, e: Endianness) -> &'static FormatInfo {
-        use mem::{align_of, size_of};
         use FormatType::*;
+        use mem::{align_of, size_of};
         macro_rules! native_info {
             ($t:ty) => {{
                 &FormatInfo {
diff --git a/vm/src/builtins/asyncgenerator.rs b/vm/src/builtins/asyncgenerator.rs
index f9ed4719d8..3aee327e5b 100644
--- a/vm/src/builtins/asyncgenerator.rs
+++ b/vm/src/builtins/asyncgenerator.rs
@@ -1,5 +1,6 @@
 use super::{PyCode, PyGenericAlias, PyStrRef, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     builtins::PyBaseExceptionRef,
     class::PyClassImpl,
     coroutine::Coro,
@@ -7,7 +8,6 @@ use crate::{
     function::OptionalArg,
     protocol::PyIterReturn,
     types::{IterNext, Iterable, Representable, SelfIter, Unconstructible},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 use crossbeam_utils::atomic::AtomicCell;
@@ -208,7 +208,7 @@ impl PyAsyncGenASend {
             AwaitableState::Closed => {
                 return Err(vm.new_runtime_error(
                     "cannot reuse already awaited __anext__()/asend()".to_owned(),
-                ))
+                ));
             }
             AwaitableState::Iter => val, // already running, all good
             AwaitableState::Init => {
diff --git a/vm/src/builtins/bool.rs b/vm/src/builtins/bool.rs
index 63bf6cff2d..93f5f4f1de 100644
--- a/vm/src/builtins/bool.rs
+++ b/vm/src/builtins/bool.rs
@@ -1,13 +1,13 @@
 use super::{PyInt, PyStrRef, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject,
+    VirtualMachine,
     class::PyClassImpl,
     convert::{IntoPyException, ToPyObject, ToPyResult},
     function::OptionalArg,
     identifier,
     protocol::PyNumberMethods,
     types::{AsNumber, Constructor, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject,
-    VirtualMachine,
 };
 use malachite_bigint::Sign;
 use num_traits::Zero;
diff --git a/vm/src/builtins/builtin_func.rs b/vm/src/builtins/builtin_func.rs
index bc1b082bc9..ff3ef38d3a 100644
--- a/vm/src/builtins/builtin_func.rs
+++ b/vm/src/builtins/builtin_func.rs
@@ -1,10 +1,10 @@
-use super::{type_, PyStrInterned, PyStrRef, PyType};
+use super::{PyStrInterned, PyStrRef, PyType, type_};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     convert::TryFromObject,
     function::{FuncArgs, PyComparisonValue, PyMethodDef, PyMethodFlags, PyNativeFn},
     types::{Callable, Comparable, PyComparisonOp, Representable, Unconstructible},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use std::fmt;
 
diff --git a/vm/src/builtins/bytearray.rs b/vm/src/builtins/bytearray.rs
index 40e6cf7b5c..36cf8cadcd 100644
--- a/vm/src/builtins/bytearray.rs
+++ b/vm/src/builtins/bytearray.rs
@@ -4,12 +4,14 @@ use super::{
     PyType, PyTypeRef,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    VirtualMachine,
     anystr::{self, AnyStr},
     atomic_func,
     byte::{bytes_from_object, value_from_object},
     bytesinner::{
-        bytes_decode, ByteInnerFindOptions, ByteInnerNewOptions, ByteInnerPaddingOptions,
-        ByteInnerSplitOptions, ByteInnerTranslateOptions, DecodeArgs, PyBytesInner,
+        ByteInnerFindOptions, ByteInnerNewOptions, ByteInnerPaddingOptions, ByteInnerSplitOptions,
+        ByteInnerTranslateOptions, DecodeArgs, PyBytesInner, bytes_decode,
     },
     class::PyClassImpl,
     common::{
@@ -33,8 +35,6 @@ use crate::{
         DefaultConstructor, Initializer, IterNext, Iterable, PyComparisonOp, Representable,
         SelfIter, Unconstructible,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
 };
 use bstr::ByteSlice;
 use std::mem::size_of;
diff --git a/vm/src/builtins/bytes.rs b/vm/src/builtins/bytes.rs
index 1db6417836..e9f5adc8bb 100644
--- a/vm/src/builtins/bytes.rs
+++ b/vm/src/builtins/bytes.rs
@@ -2,11 +2,13 @@ use super::{
     PositionIterInternal, PyDictRef, PyIntRef, PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+    TryFromBorrowedObject, TryFromObject, VirtualMachine,
     anystr::{self, AnyStr},
     atomic_func,
     bytesinner::{
-        bytes_decode, ByteInnerFindOptions, ByteInnerNewOptions, ByteInnerPaddingOptions,
-        ByteInnerSplitOptions, ByteInnerTranslateOptions, DecodeArgs, PyBytesInner,
+        ByteInnerFindOptions, ByteInnerNewOptions, ByteInnerPaddingOptions, ByteInnerSplitOptions,
+        ByteInnerTranslateOptions, DecodeArgs, PyBytesInner, bytes_decode,
     },
     class::PyClassImpl,
     common::{hash::PyHash, lock::PyMutex},
@@ -23,8 +25,6 @@ use crate::{
         AsBuffer, AsMapping, AsNumber, AsSequence, Callable, Comparable, Constructor, Hashable,
         IterNext, Iterable, PyComparisonOp, Representable, SelfIter, Unconstructible,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-    TryFromBorrowedObject, TryFromObject, VirtualMachine,
 };
 use bstr::ByteSlice;
 use once_cell::sync::Lazy;
diff --git a/vm/src/builtins/classmethod.rs b/vm/src/builtins/classmethod.rs
index 02f836199e..94b6e0ca9f 100644
--- a/vm/src/builtins/classmethod.rs
+++ b/vm/src/builtins/classmethod.rs
@@ -1,9 +1,9 @@
 use super::{PyBoundMethod, PyStr, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     common::lock::PyMutex,
     types::{Constructor, GetDescriptor, Initializer, Representable},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 /// classmethod(function) -> method
diff --git a/vm/src/builtins/code.rs b/vm/src/builtins/code.rs
index bedd71f241..d9d8895b19 100644
--- a/vm/src/builtins/code.rs
+++ b/vm/src/builtins/code.rs
@@ -4,6 +4,7 @@
 
 use super::{PyStrRef, PyTupleRef, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     builtins::PyStrInterned,
     bytecode::{self, AsBag, BorrowedConstant, CodeFlags, Constant, ConstantBag},
     class::{PyClassImpl, StaticType},
@@ -12,7 +13,6 @@ use crate::{
     function::{FuncArgs, OptionalArg},
     source_code::OneIndexed,
     types::Representable,
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 use malachite_bigint::BigInt;
 use num_traits::Zero;
diff --git a/vm/src/builtins/complex.rs b/vm/src/builtins/complex.rs
index fb5bc5066c..e665d1e27a 100644
--- a/vm/src/builtins/complex.rs
+++ b/vm/src/builtins/complex.rs
@@ -1,5 +1,6 @@
-use super::{float, PyStr, PyType, PyTypeRef};
+use super::{PyStr, PyType, PyTypeRef, float};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     convert::{ToPyObject, ToPyResult},
     function::{
@@ -11,7 +12,6 @@ use crate::{
     protocol::PyNumberMethods,
     stdlib::warnings,
     types::{AsNumber, Comparable, Constructor, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use num_complex::Complex64;
 use num_traits::Zero;
diff --git a/vm/src/builtins/coroutine.rs b/vm/src/builtins/coroutine.rs
index db9592bd47..cca2db3293 100644
--- a/vm/src/builtins/coroutine.rs
+++ b/vm/src/builtins/coroutine.rs
@@ -1,12 +1,12 @@
 use super::{PyCode, PyStrRef, PyType};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     coroutine::Coro,
     frame::FrameRef,
     function::OptionalArg,
     protocol::PyIterReturn,
     types::{IterNext, Iterable, Representable, SelfIter, Unconstructible},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "coroutine")]
diff --git a/vm/src/builtins/descriptor.rs b/vm/src/builtins/descriptor.rs
index 4b10f63f21..9da4e1d87a 100644
--- a/vm/src/builtins/descriptor.rs
+++ b/vm/src/builtins/descriptor.rs
@@ -1,10 +1,10 @@
 use super::{PyStr, PyStrInterned, PyType};
 use crate::{
-    builtins::{builtin_func::PyNativeMethod, type_, PyTypeRef},
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
+    builtins::{PyTypeRef, builtin_func::PyNativeMethod, type_},
     class::PyClassImpl,
     function::{FuncArgs, PyMethodDef, PyMethodFlags, PySetterValue},
     types::{Callable, GetDescriptor, Representable, Unconstructible},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use rustpython_common::lock::PyRwLock;
 
diff --git a/vm/src/builtins/dict.rs b/vm/src/builtins/dict.rs
index 68567e493f..e54d2a1931 100644
--- a/vm/src/builtins/dict.rs
+++ b/vm/src/builtins/dict.rs
@@ -1,13 +1,14 @@
 use super::{
-    set::PySetInner, IterStatus, PositionIterInternal, PyBaseExceptionRef, PyGenericAlias,
-    PyMappingProxy, PySet, PyStr, PyStrRef, PyTupleRef, PyType, PyTypeRef,
+    IterStatus, PositionIterInternal, PyBaseExceptionRef, PyGenericAlias, PyMappingProxy, PySet,
+    PyStr, PyStrRef, PyTupleRef, PyType, PyTypeRef, set::PySetInner,
 };
 use crate::{
-    atomic_func,
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
+    TryFromObject, atomic_func,
     builtins::{
+        PyTuple,
         iter::{builtins_iter, builtins_reversed},
         type_::PyAttributes,
-        PyTuple,
     },
     class::{PyClassDef, PyClassImpl},
     common::ascii,
@@ -21,8 +22,6 @@ use crate::{
         Initializer, IterNext, Iterable, PyComparisonOp, Representable, SelfIter, Unconstructible,
     },
     vm::VirtualMachine,
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
-    TryFromObject,
 };
 use once_cell::sync::Lazy;
 use rustpython_common::lock::PyMutex;
diff --git a/vm/src/builtins/enumerate.rs b/vm/src/builtins/enumerate.rs
index 64d7c1ed36..aa84115074 100644
--- a/vm/src/builtins/enumerate.rs
+++ b/vm/src/builtins/enumerate.rs
@@ -3,12 +3,12 @@ use super::{
 };
 use crate::common::lock::{PyMutex, PyRwLock};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     convert::ToPyObject,
     function::OptionalArg,
     protocol::{PyIter, PyIterReturn},
     types::{Constructor, IterNext, Iterable, SelfIter},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 use malachite_bigint::BigInt;
 use num_traits::Zero;
diff --git a/vm/src/builtins/filter.rs b/vm/src/builtins/filter.rs
index 3b33ff766f..009a1b3eab 100644
--- a/vm/src/builtins/filter.rs
+++ b/vm/src/builtins/filter.rs
@@ -1,9 +1,9 @@
 use super::{PyType, PyTypeRef};
 use crate::{
+    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     protocol::{PyIter, PyIterReturn},
     types::{Constructor, IterNext, Iterable, SelfIter},
-    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "filter", traverse)]
diff --git a/vm/src/builtins/float.rs b/vm/src/builtins/float.rs
index 1cd041b7b9..e33c25cb56 100644
--- a/vm/src/builtins/float.rs
+++ b/vm/src/builtins/float.rs
@@ -1,9 +1,11 @@
 // spell-checker:ignore numer denom
 
 use super::{
-    try_bigint_to_f64, PyByteArray, PyBytes, PyInt, PyIntRef, PyStr, PyStrRef, PyType, PyTypeRef,
+    PyByteArray, PyBytes, PyInt, PyIntRef, PyStr, PyStrRef, PyType, PyTypeRef, try_bigint_to_f64,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+    TryFromBorrowedObject, TryFromObject, VirtualMachine,
     class::PyClassImpl,
     common::{float_ops, hash},
     convert::{IntoPyException, ToPyObject, ToPyResult},
@@ -14,8 +16,6 @@ use crate::{
     },
     protocol::PyNumberMethods,
     types::{AsNumber, Callable, Comparable, Constructor, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-    TryFromBorrowedObject, TryFromObject, VirtualMachine,
 };
 use malachite_bigint::{BigInt, ToBigInt};
 use num_complex::Complex64;
@@ -124,8 +124,8 @@ fn inner_divmod(v1: f64, v2: f64, vm: &VirtualMachine) -> PyResult<(f64, f64)> {
 
 pub fn float_pow(v1: f64, v2: f64, vm: &VirtualMachine) -> PyResult {
     if v1.is_zero() && v2.is_sign_negative() {
-        let msg = format!("{v1} cannot be raised to a negative power");
-        Err(vm.new_zero_division_error(msg))
+        let msg = "0.0 cannot be raised to a negative power";
+        Err(vm.new_zero_division_error(msg.to_owned()))
     } else if v1.is_sign_negative() && (v2.floor() - v2).abs() > f64::EPSILON {
         let v1 = Complex64::new(v1, 0.);
         let v2 = Complex64::new(v2, 0.);
diff --git a/vm/src/builtins/frame.rs b/vm/src/builtins/frame.rs
index 3cc7d788fb..1fd031984a 100644
--- a/vm/src/builtins/frame.rs
+++ b/vm/src/builtins/frame.rs
@@ -4,11 +4,11 @@
 
 use super::{PyCode, PyDictRef, PyIntRef, PyStrRef};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     frame::{Frame, FrameRef},
     function::PySetterValue,
     types::{Representable, Unconstructible},
-    AsObject, Context, Py, PyObjectRef, PyRef, PyResult, VirtualMachine,
 };
 use num_traits::Zero;
 
diff --git a/vm/src/builtins/function.rs b/vm/src/builtins/function.rs
index eb5a142f0c..63cf8ac5c3 100644
--- a/vm/src/builtins/function.rs
+++ b/vm/src/builtins/function.rs
@@ -2,8 +2,8 @@
 mod jitfunc;
 
 use super::{
-    tuple::PyTupleTyped, PyAsyncGen, PyCode, PyCoroutine, PyDictRef, PyGenerator, PyStr, PyStrRef,
-    PyTupleRef, PyType, PyTypeRef,
+    PyAsyncGen, PyCode, PyCoroutine, PyDictRef, PyGenerator, PyStr, PyStrRef, PyTupleRef, PyType,
+    PyTypeRef, tuple::PyTupleTyped,
 };
 #[cfg(feature = "jit")]
 use crate::common::lock::OnceCell;
@@ -12,6 +12,7 @@ use crate::convert::ToPyObject;
 use crate::function::ArgMapping;
 use crate::object::{Traverse, TraverseFn};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     bytecode,
     class::PyClassImpl,
     frame::Frame,
@@ -20,7 +21,6 @@ use crate::{
     types::{
         Callable, Comparable, Constructor, GetAttr, GetDescriptor, PyComparisonOp, Representable,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use itertools::Itertools;
 #[cfg(feature = "jit")]
diff --git a/vm/src/builtins/function/jitfunc.rs b/vm/src/builtins/function/jitfunc.rs
index d46458fc65..a46d9aa0f3 100644
--- a/vm/src/builtins/function/jitfunc.rs
+++ b/vm/src/builtins/function/jitfunc.rs
@@ -1,9 +1,9 @@
 use crate::{
-    builtins::{bool_, float, int, PyBaseExceptionRef, PyDictRef, PyFunction, PyStrInterned},
+    AsObject, Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
+    builtins::{PyBaseExceptionRef, PyDictRef, PyFunction, PyStrInterned, bool_, float, int},
     bytecode::CodeFlags,
     convert::ToPyObject,
     function::FuncArgs,
-    AsObject, Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 use num_traits::ToPrimitive;
 use rustpython_jit::{AbiValue, Args, CompiledCode, JitArgumentError, JitType};
diff --git a/vm/src/builtins/generator.rs b/vm/src/builtins/generator.rs
index e0ec77006d..db9c263cb2 100644
--- a/vm/src/builtins/generator.rs
+++ b/vm/src/builtins/generator.rs
@@ -4,13 +4,13 @@
 
 use super::{PyCode, PyStrRef, PyType};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     coroutine::Coro,
     frame::FrameRef,
     function::OptionalArg,
     protocol::PyIterReturn,
     types::{IterNext, Iterable, Representable, SelfIter, Unconstructible},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "generator")]
diff --git a/vm/src/builtins/genericalias.rs b/vm/src/builtins/genericalias.rs
index 2746b03128..57c97ba62b 100644
--- a/vm/src/builtins/genericalias.rs
+++ b/vm/src/builtins/genericalias.rs
@@ -2,7 +2,8 @@ use once_cell::sync::Lazy;
 
 use super::type_;
 use crate::{
-    atomic_func,
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    VirtualMachine, atomic_func,
     builtins::{PyList, PyStr, PyTuple, PyTupleRef, PyType, PyTypeRef},
     class::PyClassImpl,
     common::hash,
@@ -13,8 +14,6 @@ use crate::{
         AsMapping, AsNumber, Callable, Comparable, Constructor, GetAttr, Hashable, PyComparisonOp,
         Representable,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
 };
 use std::fmt;
 
diff --git a/vm/src/builtins/getset.rs b/vm/src/builtins/getset.rs
index 603ec021e2..c2e11b770a 100644
--- a/vm/src/builtins/getset.rs
+++ b/vm/src/builtins/getset.rs
@@ -3,10 +3,10 @@
 */
 use super::{PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     function::{IntoPyGetterFunc, IntoPySetterFunc, PyGetterFunc, PySetterFunc, PySetterValue},
     types::{GetDescriptor, Unconstructible},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "getset_descriptor")]
diff --git a/vm/src/builtins/int.rs b/vm/src/builtins/int.rs
index eb05b4394a..db9c5ea4ed 100644
--- a/vm/src/builtins/int.rs
+++ b/vm/src/builtins/int.rs
@@ -1,5 +1,7 @@
-use super::{float, PyByteArray, PyBytes, PyStr, PyType, PyTypeRef};
+use super::{PyByteArray, PyBytes, PyStr, PyType, PyTypeRef, float};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
+    TryFromBorrowedObject, VirtualMachine,
     builtins::PyStrRef,
     bytesinner::PyBytesInner,
     class::PyClassImpl,
@@ -14,8 +16,6 @@ use crate::{
     },
     protocol::PyNumberMethods,
     types::{AsNumber, Comparable, Constructor, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
-    TryFromBorrowedObject, VirtualMachine,
 };
 use malachite_bigint::{BigInt, Sign};
 use num_integer::Integer;
@@ -109,11 +109,7 @@ fn inner_pow(int1: &BigInt, int2: &BigInt, vm: &VirtualMachine) -> PyResult {
         } else if int1.is_zero() {
             0
         } else if int1 == &BigInt::from(-1) {
-            if int2.is_odd() {
-                -1
-            } else {
-                1
-            }
+            if int2.is_odd() { -1 } else { 1 }
         } else {
             // missing feature: BigInt exp
             // practically, exp over u64 is not possible to calculate anyway
@@ -426,11 +422,7 @@ impl PyInt {
                     // based on rust-num/num-integer#10, should hopefully be published soon
                     fn normalize(a: BigInt, n: &BigInt) -> BigInt {
                         let a = a % n;
-                        if a.is_negative() {
-                            a + n
-                        } else {
-                            a
-                        }
+                        if a.is_negative() { a + n } else { a }
                     }
                     fn inverse(a: BigInt, n: &BigInt) -> Option<BigInt> {
                         use num_integer::*;
@@ -642,7 +634,7 @@ impl PyInt {
             Sign::Minus if !signed => {
                 return Err(
                     vm.new_overflow_error("can't convert negative int to unsigned".to_owned())
-                )
+                );
             }
             Sign::NoSign => return Ok(vec![0u8; byte_len].into()),
             _ => {}
diff --git a/vm/src/builtins/iter.rs b/vm/src/builtins/iter.rs
index 2fed23a5c4..5a47abfac7 100644
--- a/vm/src/builtins/iter.rs
+++ b/vm/src/builtins/iter.rs
@@ -4,12 +4,12 @@
 
 use super::{PyInt, PyTupleRef, PyType};
 use crate::{
+    Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     function::ArgCallable,
     object::{Traverse, TraverseFn},
     protocol::{PyIterReturn, PySequence, PySequenceMethods},
     types::{IterNext, Iterable, SelfIter},
-    Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 use rustpython_common::{
     lock::{PyMutex, PyRwLock, PyRwLockUpgradableReadGuard},
@@ -28,7 +28,7 @@ pub enum IterStatus<T> {
 unsafe impl<T: Traverse> Traverse for IterStatus<T> {
     fn traverse(&self, tracer_fn: &mut TraverseFn) {
         match self {
-            IterStatus::Active(ref r) => r.traverse(tracer_fn),
+            IterStatus::Active(r) => r.traverse(tracer_fn),
             IterStatus::Exhausted => (),
         }
     }
diff --git a/vm/src/builtins/list.rs b/vm/src/builtins/list.rs
index 33d6072cd5..3b9624694e 100644
--- a/vm/src/builtins/list.rs
+++ b/vm/src/builtins/list.rs
@@ -4,6 +4,7 @@ use crate::common::lock::{
     PyMappedRwLockReadGuard, PyMutex, PyRwLock, PyRwLockReadGuard, PyRwLockWriteGuard,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
     class::PyClassImpl,
     convert::ToPyObject,
     function::{ArgSize, FuncArgs, OptionalArg, PyComparisonValue},
@@ -18,7 +19,6 @@ use crate::{
     },
     utils::collection_repr,
     vm::VirtualMachine,
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
 };
 use std::{fmt, ops::DerefMut};
 
diff --git a/vm/src/builtins/map.rs b/vm/src/builtins/map.rs
index 44bacf587e..555e38c8b9 100644
--- a/vm/src/builtins/map.rs
+++ b/vm/src/builtins/map.rs
@@ -1,11 +1,11 @@
 use super::{PyType, PyTypeRef};
 use crate::{
+    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     builtins::PyTupleRef,
     class::PyClassImpl,
     function::PosArgs,
     protocol::{PyIter, PyIterReturn},
     types::{Constructor, IterNext, Iterable, SelfIter},
-    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "map", traverse)]
diff --git a/vm/src/builtins/mappingproxy.rs b/vm/src/builtins/mappingproxy.rs
index 7b2386a39b..659562cec1 100644
--- a/vm/src/builtins/mappingproxy.rs
+++ b/vm/src/builtins/mappingproxy.rs
@@ -1,5 +1,6 @@
 use super::{PyDict, PyDictRef, PyGenericAlias, PyList, PyTuple, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     atomic_func,
     class::PyClassImpl,
     convert::ToPyObject,
@@ -10,7 +11,6 @@ use crate::{
         AsMapping, AsNumber, AsSequence, Comparable, Constructor, Iterable, PyComparisonOp,
         Representable,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use once_cell::sync::Lazy;
 
@@ -29,8 +29,8 @@ enum MappingProxyInner {
 unsafe impl Traverse for MappingProxyInner {
     fn traverse(&self, tracer_fn: &mut TraverseFn) {
         match self {
-            MappingProxyInner::Class(ref r) => r.traverse(tracer_fn),
-            MappingProxyInner::Mapping(ref arg) => arg.traverse(tracer_fn),
+            MappingProxyInner::Class(r) => r.traverse(tracer_fn),
+            MappingProxyInner::Mapping(arg) => arg.traverse(tracer_fn),
         }
     }
 }
diff --git a/vm/src/builtins/memory.rs b/vm/src/builtins/memory.rs
index dfbbdc5aaf..9426730f40 100644
--- a/vm/src/builtins/memory.rs
+++ b/vm/src/builtins/memory.rs
@@ -3,7 +3,8 @@ use super::{
     PyTupleRef, PyType, PyTypeRef,
 };
 use crate::{
-    atomic_func,
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+    TryFromBorrowedObject, TryFromObject, VirtualMachine, atomic_func,
     buffer::FormatSpec,
     bytesinner::bytes_to_hex,
     class::PyClassImpl,
@@ -24,8 +25,6 @@ use crate::{
         AsBuffer, AsMapping, AsSequence, Comparable, Constructor, Hashable, IterNext, Iterable,
         PyComparisonOp, Representable, SelfIter, Unconstructible,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-    TryFromBorrowedObject, TryFromObject, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 use itertools::Itertools;
@@ -223,14 +222,16 @@ impl PyMemoryView {
     fn pos_from_multi_index(&self, indexes: &[isize], vm: &VirtualMachine) -> PyResult<usize> {
         match indexes.len().cmp(&self.desc.ndim()) {
             Ordering::Less => {
-                return Err(vm.new_not_implemented_error("sub-views are not implemented".to_owned()))
+                return Err(
+                    vm.new_not_implemented_error("sub-views are not implemented".to_owned())
+                );
             }
             Ordering::Greater => {
                 return Err(vm.new_type_error(format!(
                     "cannot index {}-dimension view with {}-element tuple",
                     self.desc.ndim(),
                     indexes.len()
-                )))
+                )));
             }
             Ordering::Equal => (),
         }
@@ -380,11 +381,7 @@ impl PyMemoryView {
                 }
             };
             ret = vm.bool_eq(&a_val, &b_val);
-            if let Ok(b) = ret {
-                !b
-            } else {
-                true
-            }
+            if let Ok(b) = ret { !b } else { true }
         });
         ret
     }
diff --git a/vm/src/builtins/module.rs b/vm/src/builtins/module.rs
index de55b9deae..8c8f22cf58 100644
--- a/vm/src/builtins/module.rs
+++ b/vm/src/builtins/module.rs
@@ -1,11 +1,11 @@
 use super::{PyDictRef, PyStr, PyStrRef, PyType, PyTypeRef};
 use crate::{
-    builtins::{pystr::AsPyStr, PyStrInterned},
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
+    builtins::{PyStrInterned, pystr::AsPyStr},
     class::PyClassImpl,
     convert::ToPyObject,
     function::{FuncArgs, PyMethodDef},
     types::{GetAttr, Initializer, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "module")]
@@ -183,11 +183,12 @@ impl Initializer for PyModule {
     type Args = ModuleInitArgs;
 
     fn init(zelf: PyRef<Self>, args: Self::Args, vm: &VirtualMachine) -> PyResult<()> {
-        debug_assert!(zelf
-            .class()
-            .slots
-            .flags
-            .has_feature(crate::types::PyTypeFlags::HAS_DICT));
+        debug_assert!(
+            zelf.class()
+                .slots
+                .flags
+                .has_feature(crate::types::PyTypeFlags::HAS_DICT)
+        );
         zelf.init_dict(vm.ctx.intern_str(args.name.as_str()), args.doc, vm);
         Ok(())
     }
diff --git a/vm/src/builtins/namespace.rs b/vm/src/builtins/namespace.rs
index 441fd014f0..38146baa72 100644
--- a/vm/src/builtins/namespace.rs
+++ b/vm/src/builtins/namespace.rs
@@ -1,5 +1,6 @@
-use super::{tuple::IntoPyTuple, PyTupleRef, PyType};
+use super::{PyTupleRef, PyType, tuple::IntoPyTuple};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     builtins::PyDict,
     class::PyClassImpl,
     function::{FuncArgs, PyComparisonValue},
@@ -7,7 +8,6 @@ use crate::{
     types::{
         Comparable, Constructor, DefaultConstructor, Initializer, PyComparisonOp, Representable,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 /// A simple attribute-based namespace.
diff --git a/vm/src/builtins/object.rs b/vm/src/builtins/object.rs
index f783ee017c..cce1422d56 100644
--- a/vm/src/builtins/object.rs
+++ b/vm/src/builtins/object.rs
@@ -2,11 +2,11 @@ use super::{PyDictRef, PyList, PyStr, PyStrRef, PyType, PyTypeRef};
 use crate::common::hash::PyHash;
 use crate::types::PyTypeFlags;
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     convert::ToPyResult,
     function::{Either, FuncArgs, PyArithmeticValue, PyComparisonValue, PySetterValue},
     types::{Constructor, PyComparisonOp},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 use itertools::Itertools;
 
@@ -113,7 +113,7 @@ fn object_getstate_default(obj: &PyObject, required: bool, vm: &VirtualMachine)
     //     ));
     // }
 
-    let state = if obj.dict().map_or(true, |d| d.is_empty()) {
+    let state = if obj.dict().is_none_or(|d| d.is_empty()) {
         vm.ctx.none()
     } else {
         // let state = object_get_dict(obj.clone(), obj.ctx()).unwrap();
diff --git a/vm/src/builtins/property.rs b/vm/src/builtins/property.rs
index 61e1ff1692..5bfae5a081 100644
--- a/vm/src/builtins/property.rs
+++ b/vm/src/builtins/property.rs
@@ -5,10 +5,10 @@ use super::{PyStrRef, PyType, PyTypeRef};
 use crate::common::lock::PyRwLock;
 use crate::function::{IntoFuncArgs, PosArgs};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     function::{FuncArgs, PySetterValue},
     types::{Constructor, GetDescriptor, Initializer},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "property", traverse)]
diff --git a/vm/src/builtins/range.rs b/vm/src/builtins/range.rs
index 602ea2d37f..b542a5f191 100644
--- a/vm/src/builtins/range.rs
+++ b/vm/src/builtins/range.rs
@@ -1,8 +1,9 @@
 use super::{
-    builtins_iter, tuple::tuple_hash, PyInt, PyIntRef, PySlice, PyTupleRef, PyType, PyTypeRef,
+    PyInt, PyIntRef, PySlice, PyTupleRef, PyType, PyTypeRef, builtins_iter, tuple::tuple_hash,
 };
 use crate::{
-    atomic_func,
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    VirtualMachine, atomic_func,
     class::PyClassImpl,
     common::hash::PyHash,
     function::{ArgIndex, FuncArgs, OptionalArg, PyComparisonValue},
@@ -11,8 +12,6 @@ use crate::{
         AsMapping, AsSequence, Comparable, Hashable, IterNext, Iterable, PyComparisonOp,
         Representable, SelfIter, Unconstructible,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 use malachite_bigint::{BigInt, Sign};
diff --git a/vm/src/builtins/set.rs b/vm/src/builtins/set.rs
index 1ab1fe21cf..62a66c89b4 100644
--- a/vm/src/builtins/set.rs
+++ b/vm/src/builtins/set.rs
@@ -2,10 +2,11 @@
  * Builtin set type with a sequence of unique items.
  */
 use super::{
-    builtins_iter, IterStatus, PositionIterInternal, PyDict, PyDictRef, PyGenericAlias, PyTupleRef,
-    PyType, PyTypeRef,
+    IterStatus, PositionIterInternal, PyDict, PyDictRef, PyGenericAlias, PyTupleRef, PyType,
+    PyTypeRef, builtins_iter,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
     atomic_func,
     class::PyClassImpl,
     common::{ascii, hash::PyHash, lock::PyMutex, rc::PyRc},
@@ -21,7 +22,6 @@ use crate::{
     },
     utils::collection_repr,
     vm::VirtualMachine,
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
 };
 use once_cell::sync::Lazy;
 use rustpython_common::{
diff --git a/vm/src/builtins/singletons.rs b/vm/src/builtins/singletons.rs
index 65b171a262..da0c718c46 100644
--- a/vm/src/builtins/singletons.rs
+++ b/vm/src/builtins/singletons.rs
@@ -1,10 +1,10 @@
 use super::{PyStrRef, PyType, PyTypeRef};
 use crate::{
+    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     convert::ToPyObject,
     protocol::PyNumberMethods,
     types::{AsNumber, Constructor, Representable},
-    Context, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "NoneType")]
diff --git a/vm/src/builtins/slice.rs b/vm/src/builtins/slice.rs
index 5da3649115..4194360f4a 100644
--- a/vm/src/builtins/slice.rs
+++ b/vm/src/builtins/slice.rs
@@ -2,13 +2,13 @@
 // spell-checker:ignore sliceobject
 use super::{PyStrRef, PyTupleRef, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     common::hash::{PyHash, PyUHash},
     convert::ToPyObject,
     function::{ArgIndex, FuncArgs, OptionalArg, PyComparisonValue},
     sliceable::SaturatedSlice,
     types::{Comparable, Constructor, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use malachite_bigint::{BigInt, ToBigInt};
 use num_traits::{One, Signed, Zero};
@@ -264,11 +264,7 @@ impl Comparable for PySlice {
                 let eq = vm.identical_or_equal(zelf.start_ref(vm), other.start_ref(vm))?
                     && vm.identical_or_equal(&zelf.stop, &other.stop)?
                     && vm.identical_or_equal(zelf.step_ref(vm), other.step_ref(vm))?;
-                if op == PyComparisonOp::Ne {
-                    !eq
-                } else {
-                    eq
-                }
+                if op == PyComparisonOp::Ne { !eq } else { eq }
             }
             PyComparisonOp::Gt | PyComparisonOp::Ge => None
                 .or_else(|| {
diff --git a/vm/src/builtins/staticmethod.rs b/vm/src/builtins/staticmethod.rs
index 59a5b18b5d..8e2333da7f 100644
--- a/vm/src/builtins/staticmethod.rs
+++ b/vm/src/builtins/staticmethod.rs
@@ -1,10 +1,10 @@
 use super::{PyStr, PyType, PyTypeRef};
 use crate::{
+    Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     common::lock::PyMutex,
     function::FuncArgs,
     types::{Callable, Constructor, GetDescriptor, Initializer, Representable},
-    Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "staticmethod", traverse)]
diff --git a/vm/src/builtins/str.rs b/vm/src/builtins/str.rs
index c0a096b211..bf9a9f679c 100644
--- a/vm/src/builtins/str.rs
+++ b/vm/src/builtins/str.rs
@@ -1,10 +1,12 @@
 use super::{
+    PositionIterInternal, PyBytesRef, PyDict, PyTupleRef, PyType, PyTypeRef,
     int::{PyInt, PyIntRef},
     iter::IterStatus::{self, Exhausted},
-    PositionIterInternal, PyBytesRef, PyDict, PyTupleRef, PyType, PyTypeRef,
 };
 use crate::{
-    anystr::{self, adjust_indices, AnyStr, AnyStrContainer, AnyStrWrapper},
+    AsObject, Context, Py, PyExact, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
+    TryFromBorrowedObject, VirtualMachine,
+    anystr::{self, AnyStr, AnyStrContainer, AnyStrWrapper, adjust_indices},
     atomic_func,
     class::PyClassImpl,
     common::str::{BorrowedStr, PyStrKind, PyStrKindData},
@@ -20,8 +22,6 @@ use crate::{
         AsMapping, AsNumber, AsSequence, Comparable, Constructor, Hashable, IterNext, Iterable,
         PyComparisonOp, Representable, SelfIter, Unconstructible,
     },
-    AsObject, Context, Py, PyExact, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, PyResult,
-    TryFromBorrowedObject, VirtualMachine,
 };
 use ascii::{AsciiStr, AsciiString};
 use bstr::ByteSlice;
@@ -313,7 +313,7 @@ impl PyStr {
     /// # Safety
     /// Given `bytes` must be ascii
     pub unsafe fn new_ascii_unchecked(bytes: Vec<u8>) -> Self {
-        Self::new_str_unchecked(bytes, PyStrKind::Ascii)
+        unsafe { Self::new_str_unchecked(bytes, PyStrKind::Ascii) }
     }
 
     pub fn new_ref(zelf: impl Into<Self>, ctx: &Context) -> PyRef<Self> {
@@ -904,11 +904,7 @@ impl PyStr {
                 '\n' => 1,
                 '\r' => {
                     let is_rn = enumerated.next_if(|(_, ch)| *ch == '\n').is_some();
-                    if is_rn {
-                        2
-                    } else {
-                        1
-                    }
+                    if is_rn { 2 } else { 1 }
                 }
                 '\x0b' | '\x0c' | '\x1c' | '\x1d' | '\x1e' | '\u{0085}' | '\u{2028}'
                 | '\u{2029}' => ch.len_utf8(),
@@ -1125,33 +1121,7 @@ impl PyStr {
 
     #[pymethod]
     fn expandtabs(&self, args: anystr::ExpandTabsArgs) -> String {
-        let tab_stop = args.tabsize();
-        let mut expanded_str = String::with_capacity(self.byte_len());
-        let mut tab_size = tab_stop;
-        let mut col_count = 0usize;
-        for ch in self.as_str().chars() {
-            match ch {
-                '\t' => {
-                    let num_spaces = tab_size - col_count;
-                    col_count += num_spaces;
-                    let expand = " ".repeat(num_spaces);
-                    expanded_str.push_str(&expand);
-                }
-                '\r' | '\n' => {
-                    expanded_str.push(ch);
-                    col_count = 0;
-                    tab_size = 0;
-                }
-                _ => {
-                    expanded_str.push(ch);
-                    col_count += 1;
-                }
-            }
-            if col_count >= tab_size {
-                tab_size += tab_stop;
-            }
-        }
-        expanded_str
+        rustpython_common::str::expandtabs(self.as_str(), args.tabsize())
     }
 
     #[pymethod]
@@ -1591,80 +1561,6 @@ impl AsRef<str> for PyExact<PyStr> {
     }
 }
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::Interpreter;
-
-    #[test]
-    fn str_title() {
-        let tests = vec![
-            (" Hello ", " hello "),
-            ("Hello ", "hello "),
-            ("Hello ", "Hello "),
-            ("Format This As Title String", "fOrMaT thIs aS titLe String"),
-            ("Format,This-As*Title;String", "fOrMaT,thIs-aS*titLe;String"),
-            ("Getint", "getInt"),
-            ("Greek Ωppercases ...", "greek ωppercases ..."),
-            ("Greek ῼitlecases ...", "greek ῳitlecases ..."),
-        ];
-        for (title, input) in tests {
-            assert_eq!(PyStr::from(input).title().as_str(), title);
-        }
-    }
-
-    #[test]
-    fn str_istitle() {
-        let pos = vec![
-            "A",
-            "A Titlecased Line",
-            "A\nTitlecased Line",
-            "A Titlecased, Line",
-            "Greek Ωppercases ...",
-            "Greek ῼitlecases ...",
-        ];
-
-        for s in pos {
-            assert!(PyStr::from(s).istitle());
-        }
-
-        let neg = vec![
-            "",
-            "a",
-            "\n",
-            "Not a capitalized String",
-            "Not\ta Titlecase String",
-            "Not--a Titlecase String",
-            "NOT",
-        ];
-        for s in neg {
-            assert!(!PyStr::from(s).istitle());
-        }
-    }
-
-    #[test]
-    fn str_maketrans_and_translate() {
-        Interpreter::without_stdlib(Default::default()).enter(|vm| {
-            let table = vm.ctx.new_dict();
-            table
-                .set_item("a", vm.ctx.new_str("🎅").into(), vm)
-                .unwrap();
-            table.set_item("b", vm.ctx.none(), vm).unwrap();
-            table
-                .set_item("c", vm.ctx.new_str(ascii!("xda")).into(), vm)
-                .unwrap();
-            let translated =
-                PyStr::maketrans(table.into(), OptionalArg::Missing, OptionalArg::Missing, vm)
-                    .unwrap();
-            let text = PyStr::from("abc");
-            let translated = text.translate(translated, vm).unwrap();
-            assert_eq!(translated, "🎅xda".to_owned());
-            let translated = text.translate(vm.ctx.new_int(3).into(), vm);
-            assert_eq!("TypeError", &*translated.unwrap_err().class().name(),);
-        })
-    }
-}
-
 impl AnyStrWrapper for PyStrRef {
     type Str = str;
     fn as_ref(&self) -> &str {
@@ -1806,3 +1702,77 @@ impl AsRef<str> for PyStrInterned {
         self.as_str()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::Interpreter;
+
+    #[test]
+    fn str_title() {
+        let tests = vec![
+            (" Hello ", " hello "),
+            ("Hello ", "hello "),
+            ("Hello ", "Hello "),
+            ("Format This As Title String", "fOrMaT thIs aS titLe String"),
+            ("Format,This-As*Title;String", "fOrMaT,thIs-aS*titLe;String"),
+            ("Getint", "getInt"),
+            ("Greek Ωppercases ...", "greek ωppercases ..."),
+            ("Greek ῼitlecases ...", "greek ῳitlecases ..."),
+        ];
+        for (title, input) in tests {
+            assert_eq!(PyStr::from(input).title().as_str(), title);
+        }
+    }
+
+    #[test]
+    fn str_istitle() {
+        let pos = vec![
+            "A",
+            "A Titlecased Line",
+            "A\nTitlecased Line",
+            "A Titlecased, Line",
+            "Greek Ωppercases ...",
+            "Greek ῼitlecases ...",
+        ];
+
+        for s in pos {
+            assert!(PyStr::from(s).istitle());
+        }
+
+        let neg = vec![
+            "",
+            "a",
+            "\n",
+            "Not a capitalized String",
+            "Not\ta Titlecase String",
+            "Not--a Titlecase String",
+            "NOT",
+        ];
+        for s in neg {
+            assert!(!PyStr::from(s).istitle());
+        }
+    }
+
+    #[test]
+    fn str_maketrans_and_translate() {
+        Interpreter::without_stdlib(Default::default()).enter(|vm| {
+            let table = vm.ctx.new_dict();
+            table
+                .set_item("a", vm.ctx.new_str("🎅").into(), vm)
+                .unwrap();
+            table.set_item("b", vm.ctx.none(), vm).unwrap();
+            table
+                .set_item("c", vm.ctx.new_str(ascii!("xda")).into(), vm)
+                .unwrap();
+            let translated =
+                PyStr::maketrans(table.into(), OptionalArg::Missing, OptionalArg::Missing, vm)
+                    .unwrap();
+            let text = PyStr::from("abc");
+            let translated = text.translate(translated, vm).unwrap();
+            assert_eq!(translated, "🎅xda".to_owned());
+            let translated = text.translate(vm.ctx.new_int(3).into(), vm);
+            assert_eq!("TypeError", &*translated.unwrap_err().class().name(),);
+        })
+    }
+}
diff --git a/vm/src/builtins/super.rs b/vm/src/builtins/super.rs
index a0192cea5c..5f363ebea5 100644
--- a/vm/src/builtins/super.rs
+++ b/vm/src/builtins/super.rs
@@ -5,11 +5,11 @@ See also [CPython source code.](https://github.com/python/cpython/blob/50b48572d
 
 use super::{PyStr, PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     class::PyClassImpl,
     common::lock::PyRwLock,
     function::{FuncArgs, IntoFuncArgs, OptionalArg},
     types::{Callable, Constructor, GetAttr, GetDescriptor, Initializer, Representable},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass(module = false, name = "super", traverse)]
diff --git a/vm/src/builtins/traceback.rs b/vm/src/builtins/traceback.rs
index 6506e95363..b0abbd006a 100644
--- a/vm/src/builtins/traceback.rs
+++ b/vm/src/builtins/traceback.rs
@@ -2,7 +2,7 @@ use rustpython_common::lock::PyMutex;
 
 use super::PyType;
 use crate::{
-    class::PyClassImpl, frame::FrameRef, source_code::LineNumber, Context, Py, PyPayload, PyRef,
+    Context, Py, PyPayload, PyRef, class::PyClassImpl, frame::FrameRef, source_code::LineNumber,
 };
 
 #[pyclass(module = false, name = "traceback", traverse)]
diff --git a/vm/src/builtins/tuple.rs b/vm/src/builtins/tuple.rs
index 9d1cc2f5ce..66cb2799a7 100644
--- a/vm/src/builtins/tuple.rs
+++ b/vm/src/builtins/tuple.rs
@@ -2,6 +2,7 @@ use super::{PositionIterInternal, PyGenericAlias, PyStrRef, PyType, PyTypeRef};
 use crate::common::{hash::PyHash, lock::PyMutex};
 use crate::object::{Traverse, TraverseFn};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
     atomic_func,
     class::PyClassImpl,
     convert::{ToPyObject, TransmuteFromObject},
@@ -17,7 +18,6 @@ use crate::{
     },
     utils::collection_repr,
     vm::VirtualMachine,
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
 };
 use once_cell::sync::Lazy;
 use std::{fmt, marker::PhantomData};
diff --git a/vm/src/builtins/type.rs b/vm/src/builtins/type.rs
index 15df5ff3c5..08a15575ed 100644
--- a/vm/src/builtins/type.rs
+++ b/vm/src/builtins/type.rs
@@ -1,16 +1,18 @@
 use super::{
-    mappingproxy::PyMappingProxy, object, union_, PyClassMethod, PyDictRef, PyList, PyStr,
-    PyStrInterned, PyStrRef, PyTuple, PyTupleRef, PyWeak,
+    PyClassMethod, PyDictRef, PyList, PyStr, PyStrInterned, PyStrRef, PyTuple, PyTupleRef, PyWeak,
+    mappingproxy::PyMappingProxy, object, union_,
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    VirtualMachine,
     builtins::{
+        PyBaseExceptionRef,
         descriptor::{
             MemberGetter, MemberKind, MemberSetter, PyDescriptorOwned, PyMemberDef,
             PyMemberDescriptor,
         },
         function::PyCellRef,
         tuple::{IntoPyTuple, PyTupleTyped},
-        PyBaseExceptionRef,
     },
     class::{PyClassImpl, StaticType},
     common::{
@@ -26,10 +28,8 @@ use crate::{
     types::{
         AsNumber, Callable, Constructor, GetAttr, PyTypeFlags, PyTypeSlots, Representable, SetAttr,
     },
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
 };
-use indexmap::{map::Entry, IndexMap};
+use indexmap::{IndexMap, map::Entry};
 use itertools::Itertools;
 use std::{borrow::Borrow, collections::HashSet, fmt, ops::Deref, pin::Pin, ptr::NonNull};
 
@@ -69,7 +69,7 @@ pub struct PointerSlot<T>(NonNull<T>);
 
 impl<T> PointerSlot<T> {
     pub unsafe fn borrow_static(&self) -> &'static T {
-        self.0.as_ref()
+        unsafe { self.0.as_ref() }
     }
 }
 
diff --git a/vm/src/builtins/union.rs b/vm/src/builtins/union.rs
index 668d87bdce..f9dc8f3131 100644
--- a/vm/src/builtins/union.rs
+++ b/vm/src/builtins/union.rs
@@ -1,5 +1,6 @@
 use super::{genericalias, type_};
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     atomic_func,
     builtins::{PyFrozenSet, PyStr, PyTuple, PyTupleRef, PyType},
     class::PyClassImpl,
@@ -8,7 +9,6 @@ use crate::{
     function::PyComparisonValue,
     protocol::{PyMappingMethods, PyNumberMethods},
     types::{AsMapping, AsNumber, Comparable, GetAttr, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use once_cell::sync::Lazy;
 use std::fmt;
diff --git a/vm/src/builtins/weakproxy.rs b/vm/src/builtins/weakproxy.rs
index f271e4cddb..d17bc75118 100644
--- a/vm/src/builtins/weakproxy.rs
+++ b/vm/src/builtins/weakproxy.rs
@@ -1,6 +1,6 @@
 use super::{PyStr, PyStrRef, PyType, PyTypeRef, PyWeak};
 use crate::{
-    atomic_func,
+    Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine, atomic_func,
     class::PyClassImpl,
     common::hash::PyHash,
     function::{OptionalArg, PyComparisonValue, PySetterValue},
@@ -10,7 +10,6 @@ use crate::{
         AsMapping, AsSequence, Comparable, Constructor, GetAttr, Hashable, IterNext, Iterable,
         PyComparisonOp, Representable, SetAttr,
     },
-    Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use once_cell::sync::Lazy;
 
diff --git a/vm/src/builtins/weakref.rs b/vm/src/builtins/weakref.rs
index 1d52225a26..9b2f248aa9 100644
--- a/vm/src/builtins/weakref.rs
+++ b/vm/src/builtins/weakref.rs
@@ -4,10 +4,10 @@ use crate::common::{
     hash::{self, PyHash},
 };
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     class::PyClassImpl,
     function::OptionalArg,
     types::{Callable, Comparable, Constructor, Hashable, PyComparisonOp, Representable},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 
 pub use crate::object::PyWeak;
diff --git a/vm/src/builtins/zip.rs b/vm/src/builtins/zip.rs
index 56c88f14c6..abd82b3ccb 100644
--- a/vm/src/builtins/zip.rs
+++ b/vm/src/builtins/zip.rs
@@ -1,11 +1,11 @@
 use super::{PyType, PyTypeRef};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     builtins::PyTupleRef,
     class::PyClassImpl,
     function::{ArgIntoBool, OptionalArg, PosArgs},
     protocol::{PyIter, PyIterReturn},
     types::{Constructor, IterNext, Iterable, SelfIter},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 use rustpython_common::atomic::{self, PyAtomic, Radium};
 
diff --git a/vm/src/bytesinner.rs b/vm/src/bytesinner.rs
index 79d4d96262..3754b75ee1 100644
--- a/vm/src/bytesinner.rs
+++ b/vm/src/bytesinner.rs
@@ -1,8 +1,9 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine,
     anystr::{self, AnyStr, AnyStrContainer, AnyStrWrapper},
     builtins::{
-        pystr, PyBaseExceptionRef, PyByteArray, PyBytes, PyBytesRef, PyInt, PyIntRef, PyStr,
-        PyStrRef, PyTypeRef,
+        PyBaseExceptionRef, PyByteArray, PyBytes, PyBytesRef, PyInt, PyIntRef, PyStr, PyStrRef,
+        PyTypeRef, pystr,
     },
     byte::bytes_from_object,
     cformat::cformat_bytes,
@@ -13,7 +14,6 @@ use crate::{
     protocol::PyBuffer,
     sequence::{SequenceExt, SequenceMutExt},
     types::PyComparisonOp,
-    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine,
 };
 use bstr::ByteSlice;
 use itertools::Itertools;
diff --git a/vm/src/cformat.rs b/vm/src/cformat.rs
index 79f4d68833..6e14034d0b 100644
--- a/vm/src/cformat.rs
+++ b/vm/src/cformat.rs
@@ -2,13 +2,13 @@
 //! as per the [Python Docs](https://docs.python.org/3/library/stdtypes.html#printf-style-string-formatting).
 
 use crate::{
+    AsObject, PyObjectRef, PyResult, TryFromBorrowedObject, TryFromObject, VirtualMachine,
     builtins::{
-        try_f64_to_bigint, tuple, PyBaseExceptionRef, PyByteArray, PyBytes, PyFloat, PyInt, PyStr,
+        PyBaseExceptionRef, PyByteArray, PyBytes, PyFloat, PyInt, PyStr, try_f64_to_bigint, tuple,
     },
     function::ArgIntoFloat,
     protocol::PyBuffer,
     stdlib::builtins,
-    AsObject, PyObjectRef, PyResult, TryFromBorrowedObject, TryFromObject, VirtualMachine,
 };
 use itertools::Itertools;
 use num_traits::cast::ToPrimitive;
diff --git a/vm/src/class.rs b/vm/src/class.rs
index 3b7f1bffcb..bc38d6bd61 100644
--- a/vm/src/class.rs
+++ b/vm/src/class.rs
@@ -5,7 +5,7 @@ use crate::{
     function::PyMethodDef,
     identifier,
     object::Py,
-    types::{hash_not_implemented, PyTypeFlags, PyTypeSlots},
+    types::{PyTypeFlags, PyTypeSlots, hash_not_implemented},
     vm::Context,
 };
 use rustpython_common::static_cell;
diff --git a/vm/src/codecs.rs b/vm/src/codecs.rs
index ff7bc48915..e104097413 100644
--- a/vm/src/codecs.rs
+++ b/vm/src/codecs.rs
@@ -1,9 +1,9 @@
 use crate::{
+    AsObject, Context, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyBytesRef, PyStr, PyStrRef, PyTuple, PyTupleRef},
     common::{ascii, lock::PyRwLock},
     convert::ToPyObject,
     function::PyMethodDef,
-    AsObject, Context, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
 };
 use std::{borrow::Cow, collections::HashMap, fmt::Write, ops::Range};
 
@@ -619,11 +619,16 @@ fn surrogatepass_errors(err: PyObjectRef, vm: &VirtualMachine) -> PyResult<(PyOb
             // Not supported, fail with original exception
             return Err(err.downcast().unwrap());
         }
+
+        debug_assert!(range.start <= 0.max(s.len() - 1));
+        debug_assert!(range.end >= 1.min(s.len()));
+        debug_assert!(range.end <= s.len());
+
         let mut c: u32 = 0;
         // Try decoding a single surrogate character. If there are more,
         // let the codec call us again.
         let p = &s.as_bytes()[range.start..];
-        if p.len() - range.start >= byte_length {
+        if p.len().overflowing_sub(range.start).0 >= byte_length {
             match standard_encoding {
                 StandardEncoding::Utf8 => {
                     if (p[0] as u32 & 0xf0) == 0xe0
@@ -637,10 +642,10 @@ fn surrogatepass_errors(err: PyObjectRef, vm: &VirtualMachine) -> PyResult<(PyOb
                     }
                 }
                 StandardEncoding::Utf16Le => {
-                    c = (p[1] as u32) << 8 | p[0] as u32;
+                    c = ((p[1] as u32) << 8) | p[0] as u32;
                 }
                 StandardEncoding::Utf16Be => {
-                    c = (p[0] as u32) << 8 | p[1] as u32;
+                    c = ((p[0] as u32) << 8) | p[1] as u32;
                 }
                 StandardEncoding::Utf32Le => {
                     c = ((p[3] as u32) << 24)
diff --git a/vm/src/convert/to_pyobject.rs b/vm/src/convert/to_pyobject.rs
index c61296fe69..840c0c65fb 100644
--- a/vm/src/convert/to_pyobject.rs
+++ b/vm/src/convert/to_pyobject.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyBaseExceptionRef, PyObjectRef, PyResult, VirtualMachine};
+use crate::{PyObjectRef, PyResult, VirtualMachine, builtins::PyBaseExceptionRef};
 
 /// Implemented by any type that can be returned from a built-in Python function.
 ///
diff --git a/vm/src/convert/try_from.rs b/vm/src/convert/try_from.rs
index 8abe829803..941e1fef2a 100644
--- a/vm/src/convert/try_from.rs
+++ b/vm/src/convert/try_from.rs
@@ -1,7 +1,7 @@
 use crate::{
+    Py, VirtualMachine,
     builtins::PyFloat,
     object::{AsObject, PyObject, PyObjectRef, PyPayload, PyRef, PyResult},
-    Py, VirtualMachine,
 };
 use num_traits::ToPrimitive;
 
diff --git a/vm/src/coroutine.rs b/vm/src/coroutine.rs
index 6d6b743310..56eb520b2c 100644
--- a/vm/src/coroutine.rs
+++ b/vm/src/coroutine.rs
@@ -1,9 +1,9 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyResult, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyStrRef},
     common::lock::PyMutex,
     frame::{ExecutionResult, FrameRef},
     protocol::PyIterReturn,
-    AsObject, PyObject, PyObjectRef, PyResult, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 
@@ -36,8 +36,8 @@ pub struct Coro {
     exception: PyMutex<Option<PyBaseExceptionRef>>, // exc_state
 }
 
-fn gen_name(gen: &PyObject, vm: &VirtualMachine) -> &'static str {
-    let typ = gen.class();
+fn gen_name(jen: &PyObject, vm: &VirtualMachine) -> &'static str {
+    let typ = jen.class();
     if typ.is(vm.ctx.types.coroutine_type) {
         "coroutine"
     } else if typ.is(vm.ctx.types.async_generator) {
@@ -67,7 +67,7 @@ impl Coro {
 
     fn run_with_context<F>(
         &self,
-        gen: &PyObject,
+        jen: &PyObject,
         vm: &VirtualMachine,
         func: F,
     ) -> PyResult<ExecutionResult>
@@ -75,7 +75,7 @@ impl Coro {
         F: FnOnce(FrameRef) -> PyResult<ExecutionResult>,
     {
         if self.running.compare_exchange(false, true).is_err() {
-            return Err(vm.new_value_error(format!("{} already executing", gen_name(gen, vm))));
+            return Err(vm.new_value_error(format!("{} already executing", gen_name(jen, vm))));
         }
 
         vm.push_exception(self.exception.lock().take());
@@ -90,7 +90,7 @@ impl Coro {
 
     pub fn send(
         &self,
-        gen: &PyObject,
+        jen: &PyObject,
         value: PyObjectRef,
         vm: &VirtualMachine,
     ) -> PyResult<PyIterReturn> {
@@ -102,22 +102,22 @@ impl Coro {
         } else if !vm.is_none(&value) {
             return Err(vm.new_type_error(format!(
                 "can't send non-None value to a just-started {}",
-                gen_name(gen, vm),
+                gen_name(jen, vm),
             )));
         } else {
             None
         };
-        let result = self.run_with_context(gen, vm, |f| f.resume(value, vm));
+        let result = self.run_with_context(jen, vm, |f| f.resume(value, vm));
         self.maybe_close(&result);
         match result {
             Ok(exec_res) => Ok(exec_res.into_iter_return(vm)),
             Err(e) => {
                 if e.fast_isinstance(vm.ctx.exceptions.stop_iteration) {
                     let err =
-                        vm.new_runtime_error(format!("{} raised StopIteration", gen_name(gen, vm)));
+                        vm.new_runtime_error(format!("{} raised StopIteration", gen_name(jen, vm)));
                     err.set_cause(Some(e));
                     Err(err)
-                } else if gen.class().is(vm.ctx.types.async_generator)
+                } else if jen.class().is(vm.ctx.types.async_generator)
                     && e.fast_isinstance(vm.ctx.exceptions.stop_async_iteration)
                 {
                     let err = vm
@@ -132,7 +132,7 @@ impl Coro {
     }
     pub fn throw(
         &self,
-        gen: &PyObject,
+        jen: &PyObject,
         exc_type: PyObjectRef,
         exc_val: PyObjectRef,
         exc_tb: PyObjectRef,
@@ -141,16 +141,16 @@ impl Coro {
         if self.closed.load() {
             return Err(vm.normalize_exception(exc_type, exc_val, exc_tb)?);
         }
-        let result = self.run_with_context(gen, vm, |f| f.gen_throw(vm, exc_type, exc_val, exc_tb));
+        let result = self.run_with_context(jen, vm, |f| f.gen_throw(vm, exc_type, exc_val, exc_tb));
         self.maybe_close(&result);
         Ok(result?.into_iter_return(vm))
     }
 
-    pub fn close(&self, gen: &PyObject, vm: &VirtualMachine) -> PyResult<()> {
+    pub fn close(&self, jen: &PyObject, vm: &VirtualMachine) -> PyResult<()> {
         if self.closed.load() {
             return Ok(());
         }
-        let result = self.run_with_context(gen, vm, |f| {
+        let result = self.run_with_context(jen, vm, |f| {
             f.gen_throw(
                 vm,
                 vm.ctx.exceptions.generator_exit.to_owned().into(),
@@ -161,7 +161,7 @@ impl Coro {
         self.closed.store(true);
         match result {
             Ok(ExecutionResult::Yield(_)) => {
-                Err(vm.new_runtime_error(format!("{} ignored GeneratorExit", gen_name(gen, vm))))
+                Err(vm.new_runtime_error(format!("{} ignored GeneratorExit", gen_name(jen, vm))))
             }
             Err(e) if !is_gen_exit(&e, vm) => Err(e),
             _ => Ok(()),
@@ -183,10 +183,10 @@ impl Coro {
     pub fn set_name(&self, name: PyStrRef) {
         *self.name.lock() = name;
     }
-    pub fn repr(&self, gen: &PyObject, id: usize, vm: &VirtualMachine) -> String {
+    pub fn repr(&self, jen: &PyObject, id: usize, vm: &VirtualMachine) -> String {
         format!(
             "<{} object {} at {:#x}>",
-            gen_name(gen, vm),
+            gen_name(jen, vm),
             self.name.lock(),
             id
         )
diff --git a/vm/src/dictdatatype.rs b/vm/src/dictdatatype.rs
index 4baeef0bfc..7c8fd23834 100644
--- a/vm/src/dictdatatype.rs
+++ b/vm/src/dictdatatype.rs
@@ -4,9 +4,9 @@
 //! And: http://code.activestate.com/recipes/578375/
 
 use crate::{
+    AsObject, Py, PyExact, PyObject, PyObjectRef, PyRefExact, PyResult, VirtualMachine,
     builtins::{PyInt, PyStr, PyStrInterned, PyStrRef},
     convert::ToPyObject,
-    AsObject, Py, PyExact, PyObject, PyObjectRef, PyRefExact, PyResult, VirtualMachine,
 };
 use crate::{
     common::{
@@ -915,7 +915,7 @@ fn str_exact<'a>(obj: &'a PyObject, vm: &VirtualMachine) -> Option<&'a PyStr> {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::{common::ascii, Interpreter};
+    use crate::{Interpreter, common::ascii};
 
     #[test]
     fn test_insert() {
diff --git a/vm/src/eval.rs b/vm/src/eval.rs
index 35f27dc9d6..4c48efc700 100644
--- a/vm/src/eval.rs
+++ b/vm/src/eval.rs
@@ -1,4 +1,4 @@
-use crate::{compiler, scope::Scope, PyResult, VirtualMachine};
+use crate::{PyResult, VirtualMachine, compiler, scope::Scope};
 
 pub fn eval(vm: &VirtualMachine, source: &str, scope: Scope, source_path: &str) -> PyResult {
     match vm.compile(source, compiler::Mode::Eval, source_path.to_owned()) {
diff --git a/vm/src/exceptions.rs b/vm/src/exceptions.rs
index 0b61c90174..5882fbe2bc 100644
--- a/vm/src/exceptions.rs
+++ b/vm/src/exceptions.rs
@@ -2,8 +2,9 @@ use self::types::{PyBaseException, PyBaseExceptionRef};
 use crate::common::lock::PyRwLock;
 use crate::object::{Traverse, TraverseFn};
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{
-        traceback::PyTracebackRef, PyNone, PyStr, PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef,
+        PyNone, PyStr, PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef, traceback::PyTracebackRef,
     },
     class::{PyClassImpl, StaticType},
     convert::{ToPyException, ToPyObject},
@@ -12,7 +13,6 @@ use crate::{
     stdlib::sys,
     suggestion::offer_suggestions,
     types::{Callable, Constructor, Initializer, Representable},
-    AsObject, Context, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 use itertools::Itertools;
@@ -374,7 +374,9 @@ fn write_traceback_entry<W: Write>(
     writeln!(
         output,
         r##"  File "{}", line {}, in {}"##,
-        filename, tb_entry.lineno, tb_entry.frame.code.obj_name
+        filename.trim_start_matches(r"\\?\"),
+        tb_entry.lineno,
+        tb_entry.frame.code.obj_name
     )?;
     print_source_line(output, filename, tb_entry.lineno.to_usize())?;
 
@@ -1175,13 +1177,13 @@ pub(super) mod types {
     use crate::common::lock::PyRwLock;
     #[cfg_attr(target_arch = "wasm32", allow(unused_imports))]
     use crate::{
+        AsObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
         builtins::{
-            traceback::PyTracebackRef, tuple::IntoPyTuple, PyInt, PyStrRef, PyTupleRef, PyTypeRef,
+            PyInt, PyStrRef, PyTupleRef, PyTypeRef, traceback::PyTracebackRef, tuple::IntoPyTuple,
         },
         convert::ToPyResult,
         function::FuncArgs,
         types::{Constructor, Initializer},
-        AsObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use itertools::Itertools;
diff --git a/vm/src/format.rs b/vm/src/format.rs
index 8109ea00f4..7e9bb54265 100644
--- a/vm/src/format.rs
+++ b/vm/src/format.rs
@@ -1,9 +1,9 @@
 use crate::{
+    PyObject, PyResult, VirtualMachine,
     builtins::PyBaseExceptionRef,
     convert::{IntoPyException, ToPyException},
     function::FuncArgs,
     stdlib::builtins,
-    PyObject, PyResult, VirtualMachine,
 };
 
 use rustpython_format::*;
diff --git a/vm/src/frame.rs b/vm/src/frame.rs
index 8fc7e171b3..7cbe25909b 100644
--- a/vm/src/frame.rs
+++ b/vm/src/frame.rs
@@ -1,11 +1,12 @@
 use crate::common::{boxvec::BoxVec, lock::PyMutex};
 use crate::{
+    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{
+        PyBaseExceptionRef, PyCode, PyCoroutine, PyDict, PyDictRef, PyGenerator, PyList, PySet,
+        PySlice, PyStr, PyStrInterned, PyStrRef, PyTraceback, PyType,
         asyncgenerator::PyAsyncGenWrappedValue,
         function::{PyCell, PyCellRef, PyFunction},
         tuple::{PyTuple, PyTupleRef, PyTupleTyped},
-        PyBaseExceptionRef, PyCode, PyCoroutine, PyDict, PyDictRef, PyGenerator, PyList, PySet,
-        PySlice, PyStr, PyStrInterned, PyStrRef, PyTraceback, PyType,
     },
     bytecode,
     convert::{IntoObject, ToPyResult},
@@ -17,7 +18,6 @@ use crate::{
     source_code::SourceLocation,
     stdlib::{builtins, typing::_typing},
     vm::{Context, PyMethod},
-    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 use indexmap::IndexMap;
 use itertools::Itertools;
@@ -277,15 +277,17 @@ impl Py<Frame> {
     }
 
     pub fn next_external_frame(&self, vm: &VirtualMachine) -> Option<FrameRef> {
-        self.f_back(vm).map(|mut back| loop {
-            back = if let Some(back) = back.to_owned().f_back(vm) {
-                back
-            } else {
-                break back;
-            };
+        self.f_back(vm).map(|mut back| {
+            loop {
+                back = if let Some(back) = back.to_owned().f_back(vm) {
+                    back
+                } else {
+                    break back;
+                };
 
-            if !back.is_internal_frame() {
-                break back;
+                if !back.is_internal_frame() {
+                    break back;
+                }
             }
         })
     }
@@ -426,19 +428,19 @@ impl ExecutingFrame<'_> {
         exc_val: PyObjectRef,
         exc_tb: PyObjectRef,
     ) -> PyResult<ExecutionResult> {
-        if let Some(gen) = self.yield_from_target() {
+        if let Some(jen) = self.yield_from_target() {
             // borrow checker shenanigans - we only need to use exc_type/val/tb if the following
             // variable is Some
-            let thrower = if let Some(coro) = self.builtin_coro(gen) {
+            let thrower = if let Some(coro) = self.builtin_coro(jen) {
                 Some(Either::A(coro))
             } else {
-                vm.get_attribute_opt(gen.to_owned(), "throw")?
+                vm.get_attribute_opt(jen.to_owned(), "throw")?
                     .map(Either::B)
             };
             if let Some(thrower) = thrower {
                 let ret = match thrower {
                     Either::A(coro) => coro
-                        .throw(gen, exc_type, exc_val, exc_tb, vm)
+                        .throw(jen, exc_type, exc_val, exc_tb, vm)
                         .to_pyresult(vm), // FIXME:
                     Either::B(meth) => meth.call((exc_type, exc_val, exc_tb), vm),
                 };
@@ -638,7 +640,7 @@ impl ExecutingFrame<'_> {
                 match res {
                     Ok(()) => {}
                     Err(e) if e.fast_isinstance(vm.ctx.exceptions.key_error) => {
-                        return Err(name_error(name, vm))
+                        return Err(name_error(name, vm));
                     }
                     Err(e) => return Err(e),
                 }
@@ -649,7 +651,7 @@ impl ExecutingFrame<'_> {
                 match self.globals.del_item(name, vm) {
                     Ok(()) => {}
                     Err(e) if e.fast_isinstance(vm.ctx.exceptions.key_error) => {
-                        return Err(name_error(name, vm))
+                        return Err(name_error(name, vm));
                     }
                     Err(e) => return Err(e),
                 }
@@ -1202,6 +1204,23 @@ impl ExecutingFrame<'_> {
                 self.push_value(type_alias.into_ref(&vm.ctx).into());
                 Ok(None)
             }
+            bytecode::Instruction::ParamSpec => {
+                let param_spec_name = self.pop_value();
+                let param_spec: PyObjectRef = _typing::make_paramspec(param_spec_name.clone())
+                    .into_ref(&vm.ctx)
+                    .into();
+                self.push_value(param_spec);
+                Ok(None)
+            }
+            bytecode::Instruction::TypeVarTuple => {
+                let type_var_tuple_name = self.pop_value();
+                let type_var_tuple: PyObjectRef =
+                    _typing::make_typevartuple(type_var_tuple_name.clone())
+                        .into_ref(&vm.ctx)
+                        .into();
+                self.push_value(type_var_tuple);
+                Ok(None)
+            }
         }
     }
 
@@ -1551,16 +1570,16 @@ impl ExecutingFrame<'_> {
 
     fn _send(
         &self,
-        gen: &PyObject,
+        jen: &PyObject,
         val: PyObjectRef,
         vm: &VirtualMachine,
     ) -> PyResult<PyIterReturn> {
-        match self.builtin_coro(gen) {
-            Some(coro) => coro.send(gen, val, vm),
+        match self.builtin_coro(jen) {
+            Some(coro) => coro.send(jen, val, vm),
             // FIXME: turn return type to PyResult<PyIterReturn> then ExecutionResult will be simplified
-            None if vm.is_none(&val) => PyIter::new(gen).next(vm),
+            None if vm.is_none(&val) => PyIter::new(jen).next(vm),
             None => {
-                let meth = gen.get_attr("send", vm)?;
+                let meth = jen.get_attr("send", vm)?;
                 PyIterReturn::from_pyresult(meth.call((val,), vm), vm)
             }
         }
diff --git a/vm/src/function/argument.rs b/vm/src/function/argument.rs
index bc60cfa253..b7fd509ef1 100644
--- a/vm/src/function/argument.rs
+++ b/vm/src/function/argument.rs
@@ -1,8 +1,8 @@
 use crate::{
+    AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyTupleRef, PyTypeRef},
     convert::ToPyObject,
     object::{Traverse, TraverseFn},
-    AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 use indexmap::IndexMap;
 use itertools::Itertools;
@@ -497,7 +497,7 @@ where
 {
     fn traverse(&self, tracer_fn: &mut TraverseFn) {
         match self {
-            OptionalArg::Present(ref o) => o.traverse(tracer_fn),
+            OptionalArg::Present(o) => o.traverse(tracer_fn),
             OptionalArg::Missing => (),
         }
     }
diff --git a/vm/src/function/arithmetic.rs b/vm/src/function/arithmetic.rs
index b40e31e1b6..9f40ca7fec 100644
--- a/vm/src/function/arithmetic.rs
+++ b/vm/src/function/arithmetic.rs
@@ -1,7 +1,7 @@
 use crate::{
+    VirtualMachine,
     convert::{ToPyObject, TryFromObject},
     object::{AsObject, PyObjectRef, PyResult},
-    VirtualMachine,
 };
 
 #[derive(result_like::OptionLike)]
diff --git a/vm/src/function/buffer.rs b/vm/src/function/buffer.rs
index f5d0dd03d6..91379e7a7f 100644
--- a/vm/src/function/buffer.rs
+++ b/vm/src/function/buffer.rs
@@ -1,9 +1,9 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, TryFromObject,
+    VirtualMachine,
     builtins::{PyStr, PyStrRef},
     common::borrow::{BorrowedValue, BorrowedValueMut},
     protocol::PyBuffer,
-    AsObject, PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, TryFromObject,
-    VirtualMachine,
 };
 
 // Python/getargs.c
diff --git a/vm/src/function/builtin.rs b/vm/src/function/builtin.rs
index bf9a5ed345..b8a408453d 100644
--- a/vm/src/function/builtin.rs
+++ b/vm/src/function/builtin.rs
@@ -1,7 +1,7 @@
 use super::{FromArgs, FuncArgs};
 use crate::{
-    convert::ToPyResult, object::PyThreadingConstraint, Py, PyPayload, PyRef, PyResult,
-    VirtualMachine,
+    Py, PyPayload, PyRef, PyResult, VirtualMachine, convert::ToPyResult,
+    object::PyThreadingConstraint,
 };
 use std::marker::PhantomData;
 
diff --git a/vm/src/function/either.rs b/vm/src/function/either.rs
index ceb79d55c9..08b96c7fe3 100644
--- a/vm/src/function/either.rs
+++ b/vm/src/function/either.rs
@@ -1,5 +1,5 @@
 use crate::{
-    convert::ToPyObject, AsObject, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
+    AsObject, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine, convert::ToPyObject,
 };
 use std::borrow::Borrow;
 
diff --git a/vm/src/function/fspath.rs b/vm/src/function/fspath.rs
index 41e99b0542..69f11eb65d 100644
--- a/vm/src/function/fspath.rs
+++ b/vm/src/function/fspath.rs
@@ -1,9 +1,9 @@
 use crate::{
+    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyBytes, PyBytesRef, PyStrRef},
     convert::{IntoPyException, ToPyObject},
     function::PyStr,
     protocol::PyBuffer,
-    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 use std::{ffi::OsStr, path::PathBuf};
 
diff --git a/vm/src/function/getset.rs b/vm/src/function/getset.rs
index 827158e834..66e668ace6 100644
--- a/vm/src/function/getset.rs
+++ b/vm/src/function/getset.rs
@@ -2,10 +2,10 @@
 
 */
 use crate::{
+    Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     convert::ToPyResult,
     function::{BorrowedParam, OwnedParam, RefParam},
     object::PyThreadingConstraint,
-    Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 
 #[derive(result_like::OptionLike, is_macro::Is, Debug)]
diff --git a/vm/src/function/method.rs b/vm/src/function/method.rs
index c8652ffb50..d3d0b85fae 100644
--- a/vm/src/function/method.rs
+++ b/vm/src/function/method.rs
@@ -1,11 +1,11 @@
 use crate::{
+    Context, Py, PyObjectRef, PyPayload, PyRef, VirtualMachine,
     builtins::{
+        PyType,
         builtin_func::{PyNativeFunction, PyNativeMethod},
         descriptor::PyMethodDescriptor,
-        PyType,
     },
     function::{IntoPyNativeFn, PyNativeFn},
-    Context, Py, PyObjectRef, PyPayload, PyRef, VirtualMachine,
 };
 
 bitflags::bitflags! {
@@ -274,7 +274,7 @@ impl HeapMethodDef {
 
 impl Py<HeapMethodDef> {
     pub(crate) unsafe fn method(&self) -> &'static PyMethodDef {
-        &*(&self.method as *const _)
+        unsafe { &*(&self.method as *const _) }
     }
 
     pub fn build_function(&self, vm: &VirtualMachine) -> PyRef<PyNativeFunction> {
diff --git a/vm/src/function/mod.rs b/vm/src/function/mod.rs
index 3bd6d0f74c..8e517f6ed5 100644
--- a/vm/src/function/mod.rs
+++ b/vm/src/function/mod.rs
@@ -15,7 +15,7 @@ pub use argument::{
 };
 pub use arithmetic::{PyArithmeticValue, PyComparisonValue};
 pub use buffer::{ArgAsciiBuffer, ArgBytesLike, ArgMemoryBuffer, ArgStrOrBytesLike};
-pub use builtin::{static_func, static_raw_func, IntoPyNativeFn, PyNativeFn};
+pub use builtin::{IntoPyNativeFn, PyNativeFn, static_func, static_raw_func};
 pub use either::Either;
 pub use fspath::FsPath;
 pub use getset::PySetterValue;
@@ -24,7 +24,7 @@ pub use method::{HeapMethodDef, PyMethodDef, PyMethodFlags};
 pub use number::{ArgIndex, ArgIntoBool, ArgIntoComplex, ArgIntoFloat, ArgPrimitiveIndex, ArgSize};
 pub use protocol::{ArgCallable, ArgIterable, ArgMapping, ArgSequence};
 
-use crate::{builtins::PyStr, convert::TryFromBorrowedObject, PyObject, PyResult, VirtualMachine};
+use crate::{PyObject, PyResult, VirtualMachine, builtins::PyStr, convert::TryFromBorrowedObject};
 use builtin::{BorrowedParam, OwnedParam, RefParam};
 
 #[derive(Clone, Copy, PartialEq, Eq)]
diff --git a/vm/src/function/number.rs b/vm/src/function/number.rs
index 5f23543395..0e36f57ad1 100644
--- a/vm/src/function/number.rs
+++ b/vm/src/function/number.rs
@@ -1,5 +1,5 @@
 use super::argument::OptionalArg;
-use crate::{builtins::PyIntRef, AsObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine};
+use crate::{AsObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine, builtins::PyIntRef};
 use malachite_bigint::BigInt;
 use num_complex::Complex64;
 use num_traits::PrimInt;
diff --git a/vm/src/function/protocol.rs b/vm/src/function/protocol.rs
index 295332e480..4b7e4c4cef 100644
--- a/vm/src/function/protocol.rs
+++ b/vm/src/function/protocol.rs
@@ -1,12 +1,12 @@
 use super::IntoFuncArgs;
 use crate::{
-    builtins::{iter::PySequenceIterator, PyDict, PyDictRef},
+    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
+    builtins::{PyDict, PyDictRef, iter::PySequenceIterator},
     convert::ToPyObject,
     identifier,
     object::{Traverse, TraverseFn},
     protocol::{PyIter, PyIterIter, PyMapping, PyMappingMethods},
     types::{AsMapping, GenericMethod},
-    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
 };
 use std::{borrow::Borrow, marker::PhantomData, ops::Deref};
 
diff --git a/vm/src/import.rs b/vm/src/import.rs
index f14ae31ef4..860f0b8a16 100644
--- a/vm/src/import.rs
+++ b/vm/src/import.rs
@@ -2,13 +2,12 @@
  * Import mechanics
  */
 use crate::{
-    builtins::{list, traceback::PyTraceback, PyBaseExceptionRef, PyCode},
+    AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    builtins::{PyBaseExceptionRef, PyCode, list, traceback::PyTraceback},
     scope::Scope,
     version::get_git_revision,
-    vm::{thread, VirtualMachine},
-    AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    vm::{VirtualMachine, thread},
 };
-use rand::Rng;
 
 pub(crate) fn init_importlib_base(vm: &mut VirtualMachine) -> PyResult<PyObjectRef> {
     flame_guard!("init importlib");
@@ -50,7 +49,7 @@ pub(crate) fn init_importlib_package(vm: &VirtualMachine, importlib: PyObjectRef
         let mut magic = get_git_revision().into_bytes();
         magic.truncate(4);
         if magic.len() != 4 {
-            magic = rand::thread_rng().gen::<[u8; 4]>().to_vec();
+            magic = rand::random::<[u8; 4]>().to_vec();
         }
         let magic: PyObjectRef = vm.ctx.new_bytes(magic).into();
         importlib_external.set_attr("MAGIC_NUMBER", magic, vm)?;
diff --git a/vm/src/intern.rs b/vm/src/intern.rs
index 45bd45d965..10aaa53454 100644
--- a/vm/src/intern.rs
+++ b/vm/src/intern.rs
@@ -1,8 +1,8 @@
 use crate::{
+    AsObject, Py, PyExact, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, VirtualMachine,
     builtins::{PyStr, PyStrInterned, PyTypeRef},
     common::lock::PyRwLock,
     convert::ToPyObject,
-    AsObject, Py, PyExact, PyObject, PyObjectRef, PyPayload, PyRef, PyRefExact, VirtualMachine,
 };
 use std::{
     borrow::{Borrow, ToOwned},
@@ -117,7 +117,7 @@ impl CachedPyStrRef {
     /// the given cache must be alive while returned reference is alive
     #[inline]
     unsafe fn as_interned_str(&self) -> &'static PyStrInterned {
-        std::mem::transmute_copy(self)
+        unsafe { std::mem::transmute_copy(self) }
     }
 
     #[inline]
diff --git a/vm/src/iter.rs b/vm/src/iter.rs
index 497dc20adc..1e13243792 100644
--- a/vm/src/iter.rs
+++ b/vm/src/iter.rs
@@ -1,4 +1,4 @@
-use crate::{types::PyComparisonOp, vm::VirtualMachine, PyObjectRef, PyResult};
+use crate::{PyObjectRef, PyResult, types::PyComparisonOp, vm::VirtualMachine};
 use itertools::Itertools;
 
 pub trait PyExactSizeIterator<'a>: ExactSizeIterator<Item = &'a PyObjectRef> + Sized {
diff --git a/vm/src/object/core.rs b/vm/src/object/core.rs
index b326935464..481111532a 100644
--- a/vm/src/object/core.rs
+++ b/vm/src/object/core.rs
@@ -11,9 +11,9 @@
 //! PyRef<PyWeak> may looking like to be called as PyObjectWeak by the rule,
 //! but not to do to remember it is a PyRef object.
 use super::{
+    PyAtomicRef,
     ext::{AsObject, PyRefExact, PyResult},
     payload::PyObjectPayload,
-    PyAtomicRef,
 };
 use crate::object::traverse::{Traverse, TraverseFn};
 use crate::object::traverse_object::PyObjVTable;
@@ -77,19 +77,19 @@ use std::{
 pub(super) struct Erased;
 
 pub(super) unsafe fn drop_dealloc_obj<T: PyObjectPayload>(x: *mut PyObject) {
-    drop(Box::from_raw(x as *mut PyInner<T>));
+    drop(unsafe { Box::from_raw(x as *mut PyInner<T>) });
 }
 pub(super) unsafe fn debug_obj<T: PyObjectPayload>(
     x: &PyObject,
     f: &mut fmt::Formatter,
 ) -> fmt::Result {
-    let x = &*(x as *const PyObject as *const PyInner<T>);
+    let x = unsafe { &*(x as *const PyObject as *const PyInner<T>) };
     fmt::Debug::fmt(x, f)
 }
 
 /// Call `try_trace` on payload
 pub(super) unsafe fn try_trace_obj<T: PyObjectPayload>(x: &PyObject, tracer_fn: &mut TraverseFn) {
-    let x = &*(x as *const PyObject as *const PyInner<T>);
+    let x = unsafe { &*(x as *const PyObject as *const PyInner<T>) };
     let payload = &x.payload;
     payload.try_traverse(tracer_fn)
 }
@@ -278,7 +278,7 @@ impl WeakRefList {
     }
 
     unsafe fn dealloc(ptr: NonNull<PyMutex<WeakListInner>>) {
-        drop(Box::from_raw(ptr.as_ptr()));
+        drop(unsafe { Box::from_raw(ptr.as_ptr()) });
     }
 
     fn get_weak_references(&self) -> Vec<PyRef<PyWeak>> {
@@ -317,12 +317,14 @@ unsafe impl Link for WeakLink {
 
     #[inline(always)]
     unsafe fn from_raw(ptr: NonNull<Self::Target>) -> Self::Handle {
-        PyRef::from_raw(ptr.as_ptr())
+        // SAFETY: requirements forwarded from caller
+        unsafe { PyRef::from_raw(ptr.as_ptr()) }
     }
 
     #[inline(always)]
     unsafe fn pointers(target: NonNull<Self::Target>) -> NonNull<Pointers<Self::Target>> {
-        NonNull::new_unchecked(&raw mut (*target.as_ptr()).0.payload.pointers)
+        // SAFETY: requirements forwarded from caller
+        unsafe { NonNull::new_unchecked(&raw mut (*target.as_ptr()).0.payload.pointers) }
     }
 }
 
@@ -352,7 +354,7 @@ impl PyWeak {
             if !obj_ptr.as_ref().0.ref_count.safe_inc() {
                 return None;
             }
-            Some(PyObjectRef::from_raw(obj_ptr.as_ptr()))
+            Some(PyObjectRef::from_raw(obj_ptr))
         }
     }
 
@@ -506,8 +508,8 @@ impl ToOwned for PyObject {
 
 impl PyObjectRef {
     #[inline(always)]
-    pub fn into_raw(self) -> *const PyObject {
-        let ptr = self.as_raw();
+    pub fn into_raw(self) -> NonNull<PyObject> {
+        let ptr = self.ptr;
         std::mem::forget(self);
         ptr
     }
@@ -518,10 +520,8 @@ impl PyObjectRef {
     /// dropped more than once due to mishandling the reference count by calling this function
     /// too many times.
     #[inline(always)]
-    pub unsafe fn from_raw(ptr: *const PyObject) -> Self {
-        Self {
-            ptr: NonNull::new_unchecked(ptr as *mut PyObject),
-        }
+    pub unsafe fn from_raw(ptr: NonNull<PyObject>) -> Self {
+        Self { ptr }
     }
 
     /// Attempt to downcast this reference to a subclass.
@@ -567,7 +567,8 @@ impl PyObjectRef {
     #[inline(always)]
     pub unsafe fn downcast_unchecked_ref<T: PyObjectPayload>(&self) -> &Py<T> {
         debug_assert!(self.payload_is::<T>());
-        &*(self as *const PyObjectRef as *const PyRef<T>)
+        // SAFETY: requirements forwarded from caller
+        unsafe { &*(self as *const PyObjectRef as *const PyRef<T>) }
     }
 
     // ideally we'd be able to define these in pyobject.rs, but method visibility rules are weird
@@ -752,7 +753,8 @@ impl PyObject {
     #[inline(always)]
     pub unsafe fn downcast_unchecked_ref<T: PyObjectPayload>(&self) -> &Py<T> {
         debug_assert!(self.payload_is::<T>());
-        &*(self as *const PyObject as *const Py<T>)
+        // SAFETY: requirements forwarded from caller
+        unsafe { &*(self as *const PyObject as *const Py<T>) }
     }
 
     #[inline(always)]
@@ -814,13 +816,13 @@ impl PyObject {
     /// Can only be called when ref_count has dropped to zero. `ptr` must be valid
     #[inline(never)]
     unsafe fn drop_slow(ptr: NonNull<PyObject>) {
-        if let Err(()) = ptr.as_ref().drop_slow_inner() {
+        if let Err(()) = unsafe { ptr.as_ref().drop_slow_inner() } {
             // abort drop for whatever reason
             return;
         }
-        let drop_dealloc = ptr.as_ref().0.vtable.drop_dealloc;
+        let drop_dealloc = unsafe { ptr.as_ref().0.vtable.drop_dealloc };
         // call drop only when there are no references in scope - stacked borrows stuff
-        drop_dealloc(ptr.as_ptr())
+        unsafe { drop_dealloc(ptr.as_ptr()) }
     }
 
     /// # Safety
@@ -1022,7 +1024,7 @@ impl<T: PyObjectPayload> PyRef<T> {
     #[inline(always)]
     pub(crate) unsafe fn from_raw(raw: *const Py<T>) -> Self {
         Self {
-            ptr: NonNull::new_unchecked(raw as *mut _),
+            ptr: unsafe { NonNull::new_unchecked(raw as *mut _) },
         }
     }
 
diff --git a/vm/src/object/ext.rs b/vm/src/object/ext.rs
index f7247bc5e0..8c6d367583 100644
--- a/vm/src/object/ext.rs
+++ b/vm/src/object/ext.rs
@@ -7,12 +7,18 @@ use crate::common::{
     lock::PyRwLockReadGuard,
 };
 use crate::{
+    VirtualMachine,
     builtins::{PyBaseExceptionRef, PyStrInterned, PyType},
     convert::{IntoPyException, ToPyObject, ToPyResult, TryFromObject},
     vm::Context,
-    VirtualMachine,
 };
-use std::{borrow::Borrow, fmt, marker::PhantomData, ops::Deref, ptr::null_mut};
+use std::{
+    borrow::Borrow,
+    fmt,
+    marker::PhantomData,
+    ops::Deref,
+    ptr::{NonNull, null_mut},
+};
 
 /* Python objects and references.
 
@@ -60,7 +66,7 @@ impl<T: PyPayload> PyExact<T> {
     /// Given reference must be exact type of payload T
     #[inline(always)]
     pub unsafe fn ref_unchecked(r: &Py<T>) -> &Self {
-        &*(r as *const _ as *const Self)
+        unsafe { &*(r as *const _ as *const Self) }
     }
 }
 
@@ -294,7 +300,7 @@ impl<T: PyObjectPayload> PyAtomicRef<T> {
     pub unsafe fn swap(&self, pyref: PyRef<T>) -> PyRef<T> {
         let py = PyRef::leak(pyref) as *const Py<T> as *mut _;
         let old = Radium::swap(&self.inner, py, Ordering::AcqRel);
-        PyRef::from_raw(old.cast())
+        unsafe { PyRef::from_raw(old.cast()) }
     }
 
     pub fn swap_to_temporary_refs(&self, pyref: PyRef<T>, vm: &VirtualMachine) {
@@ -352,7 +358,7 @@ impl From<PyObjectRef> for PyAtomicRef<PyObject> {
     fn from(obj: PyObjectRef) -> Self {
         let obj = obj.into_raw();
         Self {
-            inner: Radium::new(obj as *mut _),
+            inner: Radium::new(obj.cast().as_ptr()),
             _phantom: Default::default(),
         }
     }
@@ -379,8 +385,8 @@ impl PyAtomicRef<PyObject> {
     #[must_use]
     pub unsafe fn swap(&self, obj: PyObjectRef) -> PyObjectRef {
         let obj = obj.into_raw();
-        let old = Radium::swap(&self.inner, obj as *mut _, Ordering::AcqRel);
-        PyObjectRef::from_raw(old as _)
+        let old = Radium::swap(&self.inner, obj.cast().as_ptr(), Ordering::AcqRel);
+        unsafe { PyObjectRef::from_raw(NonNull::new_unchecked(old.cast())) }
     }
 
     pub fn swap_to_temporary_refs(&self, obj: PyObjectRef, vm: &VirtualMachine) {
@@ -393,7 +399,9 @@ impl PyAtomicRef<PyObject> {
 
 impl From<Option<PyObjectRef>> for PyAtomicRef<Option<PyObject>> {
     fn from(obj: Option<PyObjectRef>) -> Self {
-        let val = obj.map(|x| x.into_raw() as *mut _).unwrap_or(null_mut());
+        let val = obj
+            .map(|x| x.into_raw().as_ptr().cast())
+            .unwrap_or(null_mut());
         Self {
             inner: Radium::new(val),
             _phantom: Default::default(),
@@ -420,11 +428,11 @@ impl PyAtomicRef<Option<PyObject>> {
     /// until no more reference can be used via PyAtomicRef::deref()
     #[must_use]
     pub unsafe fn swap(&self, obj: Option<PyObjectRef>) -> Option<PyObjectRef> {
-        let val = obj.map(|x| x.into_raw() as *mut _).unwrap_or(null_mut());
+        let val = obj
+            .map(|x| x.into_raw().as_ptr().cast())
+            .unwrap_or(null_mut());
         let old = Radium::swap(&self.inner, val, Ordering::AcqRel);
-        old.cast::<PyObject>()
-            .as_ref()
-            .map(|x| PyObjectRef::from_raw(x))
+        unsafe { NonNull::new(old.cast::<PyObject>()).map(|x| PyObjectRef::from_raw(x)) }
     }
 
     pub fn swap_to_temporary_refs(&self, obj: Option<PyObjectRef>, vm: &VirtualMachine) {
diff --git a/vm/src/object/payload.rs b/vm/src/object/payload.rs
index d5f3d6330b..6413d6ae06 100644
--- a/vm/src/object/payload.rs
+++ b/vm/src/object/payload.rs
@@ -1,9 +1,9 @@
 use crate::object::{MaybeTraverse, Py, PyObjectRef, PyRef, PyResult};
 use crate::{
+    PyRefExact,
     builtins::{PyBaseExceptionRef, PyType, PyTypeRef},
     types::PyTypeFlags,
     vm::{Context, VirtualMachine},
-    PyRefExact,
 };
 
 cfg_if::cfg_if! {
diff --git a/vm/src/object/traverse.rs b/vm/src/object/traverse.rs
index 43a039d331..5f93dc5c8b 100644
--- a/vm/src/object/traverse.rs
+++ b/vm/src/object/traverse.rs
@@ -2,7 +2,7 @@ use std::ptr::NonNull;
 
 use rustpython_common::lock::{PyMutex, PyRwLock};
 
-use crate::{function::Either, object::PyObjectPayload, AsObject, PyObject, PyObjectRef, PyRef};
+use crate::{AsObject, PyObject, PyObjectRef, PyRef, function::Either, object::PyObjectPayload};
 
 pub type TraverseFn<'a> = dyn FnMut(&PyObject) + 'a;
 
diff --git a/vm/src/object/traverse_object.rs b/vm/src/object/traverse_object.rs
index b690b80f75..682ddf4876 100644
--- a/vm/src/object/traverse_object.rs
+++ b/vm/src/object/traverse_object.rs
@@ -1,10 +1,10 @@
 use std::fmt;
 
 use crate::{
+    PyObject,
     object::{
-        debug_obj, drop_dealloc_obj, try_trace_obj, Erased, InstanceDict, PyInner, PyObjectPayload,
+        Erased, InstanceDict, PyInner, PyObjectPayload, debug_obj, drop_dealloc_obj, try_trace_obj,
     },
-    PyObject,
 };
 
 use super::{Traverse, TraverseFn};
diff --git a/vm/src/ospath.rs b/vm/src/ospath.rs
index fe26f227d1..9dda60d621 100644
--- a/vm/src/ospath.rs
+++ b/vm/src/ospath.rs
@@ -1,9 +1,9 @@
 use crate::{
+    PyObjectRef, PyResult, VirtualMachine,
     builtins::PyBaseExceptionRef,
     convert::{ToPyException, TryFromObject},
     function::FsPath,
     object::AsObject,
-    PyObjectRef, PyResult, VirtualMachine,
 };
 use std::path::{Path, PathBuf};
 
diff --git a/vm/src/protocol/buffer.rs b/vm/src/protocol/buffer.rs
index 3783ccf4b6..8692e4f78e 100644
--- a/vm/src/protocol/buffer.rs
+++ b/vm/src/protocol/buffer.rs
@@ -2,6 +2,7 @@
 //! https://docs.python.org/3/c-api/buffer.html
 
 use crate::{
+    Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject, VirtualMachine,
     common::{
         borrow::{BorrowedValue, BorrowedValueMut},
         lock::{MapImmutable, PyMutex, PyMutexGuard},
@@ -9,7 +10,6 @@ use crate::{
     object::PyObjectPayload,
     sliceable::SequenceIndexOp,
     types::Unconstructible,
-    Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject, VirtualMachine,
 };
 use itertools::Itertools;
 use std::{borrow::Cow, fmt::Debug, ops::Range};
@@ -133,8 +133,11 @@ impl PyBuffer {
     // after this function, the owner should use forget()
     // or wrap PyBuffer in the ManaullyDrop to prevent drop()
     pub(crate) unsafe fn drop_without_release(&mut self) {
-        std::ptr::drop_in_place(&mut self.obj);
-        std::ptr::drop_in_place(&mut self.desc);
+        // SAFETY: requirements forwarded from caller
+        unsafe {
+            std::ptr::drop_in_place(&mut self.obj);
+            std::ptr::drop_in_place(&mut self.desc);
+        }
     }
 }
 
diff --git a/vm/src/protocol/iter.rs b/vm/src/protocol/iter.rs
index d9c49ed15f..345914e411 100644
--- a/vm/src/protocol/iter.rs
+++ b/vm/src/protocol/iter.rs
@@ -1,8 +1,8 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
     builtins::iter::PySequenceIterator,
     convert::{ToPyObject, ToPyResult},
     object::{Traverse, TraverseFn},
-    AsObject, PyObject, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
 };
 use std::borrow::Borrow;
 use std::ops::Deref;
diff --git a/vm/src/protocol/mapping.rs b/vm/src/protocol/mapping.rs
index 986b806f6c..cbecc8762e 100644
--- a/vm/src/protocol/mapping.rs
+++ b/vm/src/protocol/mapping.rs
@@ -1,12 +1,12 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyResult, VirtualMachine,
     builtins::{
+        PyDict, PyStrInterned,
         dict::{PyDictItems, PyDictKeys, PyDictValues},
         type_::PointerSlot,
-        PyDict, PyStrInterned,
     },
     convert::ToPyResult,
     object::{Traverse, TraverseFn},
-    AsObject, PyObject, PyObjectRef, PyResult, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 
diff --git a/vm/src/protocol/number.rs b/vm/src/protocol/number.rs
index 01829bb553..65c4eaad79 100644
--- a/vm/src/protocol/number.rs
+++ b/vm/src/protocol/number.rs
@@ -3,13 +3,13 @@ use std::ops::Deref;
 use crossbeam_utils::atomic::AtomicCell;
 
 use crate::{
-    builtins::{int, PyByteArray, PyBytes, PyComplex, PyFloat, PyInt, PyIntRef, PyStr},
+    AsObject, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject,
+    VirtualMachine,
+    builtins::{PyByteArray, PyBytes, PyComplex, PyFloat, PyInt, PyIntRef, PyStr, int},
     common::int::bytes_to_int,
     function::ArgBytesLike,
     object::{Traverse, TraverseFn},
     stdlib::warnings,
-    AsObject, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject,
-    VirtualMachine,
 };
 
 pub type PyNumberUnaryFunc<R = PyObjectRef> = fn(PyNumber, &VirtualMachine) -> PyResult<R>;
diff --git a/vm/src/protocol/object.rs b/vm/src/protocol/object.rs
index 8b9c0e446c..4e69cf38a2 100644
--- a/vm/src/protocol/object.rs
+++ b/vm/src/protocol/object.rs
@@ -2,9 +2,10 @@
 //! https://docs.python.org/3/c-api/object.html
 
 use crate::{
+    AsObject, Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{
-        pystr::AsPyStr, PyAsyncGen, PyBytes, PyDict, PyDictRef, PyGenericAlias, PyInt, PyList,
-        PyStr, PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef,
+        PyAsyncGen, PyBytes, PyDict, PyDictRef, PyGenericAlias, PyInt, PyList, PyStr, PyStrRef,
+        PyTuple, PyTupleRef, PyType, PyTypeRef, pystr::AsPyStr,
     },
     bytesinner::ByteInnerNewOptions,
     common::{hash::PyHash, str::to_ascii},
@@ -14,7 +15,6 @@ use crate::{
     object::PyPayload,
     protocol::{PyIter, PyMapping, PySequence},
     types::{Constructor, PyComparisonOp},
-    AsObject, Py, PyObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 
 // RustPython doesn't need these items
diff --git a/vm/src/protocol/sequence.rs b/vm/src/protocol/sequence.rs
index 62cf828e40..46ac0c8be7 100644
--- a/vm/src/protocol/sequence.rs
+++ b/vm/src/protocol/sequence.rs
@@ -1,10 +1,10 @@
 use crate::{
-    builtins::{type_::PointerSlot, PyList, PyListRef, PySlice, PyTuple, PyTupleRef},
+    PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
+    builtins::{PyList, PyListRef, PySlice, PyTuple, PyTupleRef, type_::PointerSlot},
     convert::ToPyObject,
     function::PyArithmeticValue,
     object::{Traverse, TraverseFn},
     protocol::{PyMapping, PyNumberBinaryOp},
-    PyObject, PyObjectRef, PyPayload, PyResult, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 use itertools::Itertools;
diff --git a/vm/src/py_io.rs b/vm/src/py_io.rs
index 8091b75afc..0d7c319bc0 100644
--- a/vm/src/py_io.rs
+++ b/vm/src/py_io.rs
@@ -1,7 +1,7 @@
 use crate::{
+    PyObject, PyObjectRef, PyResult, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyBytes, PyStr},
     common::ascii,
-    PyObject, PyObjectRef, PyResult, VirtualMachine,
 };
 use std::{fmt, io, ops};
 
diff --git a/vm/src/py_serde.rs b/vm/src/py_serde.rs
index b4b12e430d..ea72879e42 100644
--- a/vm/src/py_serde.rs
+++ b/vm/src/py_serde.rs
@@ -3,7 +3,7 @@ use num_traits::sign::Signed;
 use serde::de::{DeserializeSeed, Visitor};
 use serde::ser::{Serialize, SerializeMap, SerializeSeq};
 
-use crate::builtins::{bool_, dict::PyDictRef, float, int, list::PyList, tuple::PyTuple, PyStr};
+use crate::builtins::{PyStr, bool_, dict::PyDictRef, float, int, list::PyList, tuple::PyTuple};
 use crate::{AsObject, PyObject, PyObjectRef, VirtualMachine};
 
 #[inline]
diff --git a/vm/src/scope.rs b/vm/src/scope.rs
index 47a1e5e3ff..12b878f847 100644
--- a/vm/src/scope.rs
+++ b/vm/src/scope.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyDictRef, function::ArgMapping, VirtualMachine};
+use crate::{VirtualMachine, builtins::PyDictRef, function::ArgMapping};
 use std::fmt;
 
 #[derive(Clone)]
diff --git a/vm/src/sequence.rs b/vm/src/sequence.rs
index 3f2d1e94d2..fc6e216809 100644
--- a/vm/src/sequence.rs
+++ b/vm/src/sequence.rs
@@ -1,10 +1,10 @@
 use crate::{
+    AsObject, PyObject, PyObjectRef, PyResult,
     builtins::PyIntRef,
     function::OptionalArg,
     sliceable::SequenceIndexOp,
     types::PyComparisonOp,
-    vm::{VirtualMachine, MAX_MEMORY_SIZE},
-    AsObject, PyObject, PyObjectRef, PyResult,
+    vm::{MAX_MEMORY_SIZE, VirtualMachine},
 };
 use optional::Optioned;
 use std::ops::{Deref, Range};
diff --git a/vm/src/signal.rs b/vm/src/signal.rs
index 7489282de2..346664fa24 100644
--- a/vm/src/signal.rs
+++ b/vm/src/signal.rs
@@ -69,7 +69,7 @@ pub fn assert_in_range(signum: i32, vm: &VirtualMachine) -> PyResult<()> {
 #[allow(dead_code)]
 #[cfg(not(target_arch = "wasm32"))]
 pub fn set_interrupt_ex(signum: i32, vm: &VirtualMachine) -> PyResult<()> {
-    use crate::stdlib::signal::_signal::{run_signal, SIG_DFL, SIG_IGN};
+    use crate::stdlib::signal::_signal::{SIG_DFL, SIG_IGN, run_signal};
     assert_in_range(signum, vm)?;
 
     match signum as usize {
diff --git a/vm/src/sliceable.rs b/vm/src/sliceable.rs
index 257d325651..cbc25e4e18 100644
--- a/vm/src/sliceable.rs
+++ b/vm/src/sliceable.rs
@@ -1,7 +1,7 @@
 // export through sliceable module, not slice.
 use crate::{
-    builtins::{int::PyInt, slice::PySlice},
     PyObject, PyResult, VirtualMachine,
+    builtins::{int::PyInt, slice::PySlice},
 };
 use malachite_bigint::BigInt;
 use num_traits::{Signed, ToPrimitive};
@@ -357,13 +357,8 @@ impl SaturatedSlice {
         if step == 0 {
             return Err(vm.new_value_error("slice step cannot be zero".to_owned()));
         }
-        let start = to_isize_index(vm, slice.start_ref(vm))?.unwrap_or_else(|| {
-            if step.is_negative() {
-                isize::MAX
-            } else {
-                0
-            }
-        });
+        let start = to_isize_index(vm, slice.start_ref(vm))?
+            .unwrap_or_else(|| if step.is_negative() { isize::MAX } else { 0 });
 
         let stop = to_isize_index(vm, &slice.stop(vm))?.unwrap_or_else(|| {
             if step.is_negative() {
diff --git a/vm/src/stdlib/ast.rs b/vm/src/stdlib/ast.rs
index 8b081294b9..7dd893646e 100644
--- a/vm/src/stdlib/ast.rs
+++ b/vm/src/stdlib/ast.rs
@@ -3,17 +3,17 @@
 //! This module makes use of the parser logic, and translates all ast nodes
 //! into python ast.AST objects.
 
-mod gen;
+mod r#gen;
 
 use crate::{
+    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
+    VirtualMachine,
     builtins::{self, PyDict, PyModule, PyStrRef, PyType},
     class::{PyClassImpl, StaticType},
-    compiler::core::bytecode::OpArgType,
     compiler::CompileError,
+    compiler::core::bytecode::OpArgType,
     convert::ToPyException,
     source_code::{LinearLocator, OneIndexed, SourceLocation, SourceRange},
-    AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
-    VirtualMachine,
 };
 use num_complex::Complex64;
 use num_traits::{ToPrimitive, Zero};
@@ -26,9 +26,9 @@ use rustpython_parser as parser;
 #[pymodule]
 mod _ast {
     use crate::{
+        AsObject, Context, PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyStrRef, PyTupleRef},
         function::FuncArgs,
-        AsObject, Context, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     #[pyattr]
     #[pyclass(module = "_ast", name = "AST")]
@@ -398,6 +398,6 @@ pub const PY_COMPILE_FLAGS_MASK: i32 = PY_COMPILE_FLAG_AST_ONLY
 
 pub fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = _ast::make_module(vm);
-    gen::extend_module_nodes(vm, &module);
+    r#gen::extend_module_nodes(vm, &module);
     module
 }
diff --git a/vm/src/stdlib/atexit.rs b/vm/src/stdlib/atexit.rs
index dbeda76741..b1832b5481 100644
--- a/vm/src/stdlib/atexit.rs
+++ b/vm/src/stdlib/atexit.rs
@@ -3,7 +3,7 @@ pub(crate) use atexit::make_module;
 
 #[pymodule]
 mod atexit {
-    use crate::{function::FuncArgs, AsObject, PyObjectRef, PyResult, VirtualMachine};
+    use crate::{AsObject, PyObjectRef, PyResult, VirtualMachine, function::FuncArgs};
 
     #[pyfunction]
     fn register(func: PyObjectRef, args: FuncArgs, vm: &VirtualMachine) -> PyObjectRef {
diff --git a/vm/src/stdlib/builtins.rs b/vm/src/stdlib/builtins.rs
index cc9b0a8be7..22aa11dc43 100644
--- a/vm/src/stdlib/builtins.rs
+++ b/vm/src/stdlib/builtins.rs
@@ -1,7 +1,7 @@
 //! Builtin function definitions.
 //!
 //! Implements the list of [builtin Python functions](https://docs.python.org/3/library/builtins.html).
-use crate::{builtins::PyModule, class::PyClassImpl, Py, VirtualMachine};
+use crate::{Py, VirtualMachine, builtins::PyModule, class::PyClassImpl};
 pub(crate) use builtins::{__module_def, DOC};
 pub use builtins::{ascii, print, reversed};
 
@@ -10,13 +10,14 @@ mod builtins {
     use std::io::IsTerminal;
 
     use crate::{
+        AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{
+            PyByteArray, PyBytes, PyDictRef, PyStr, PyStrRef, PyTuple, PyTupleRef, PyType,
             enumerate::PyReverseSequenceIterator,
             function::{PyCellRef, PyFunction},
             int::PyIntRef,
             iter::PyCallableIterator,
             list::{PyList, SortOptions},
-            PyByteArray, PyBytes, PyDictRef, PyStr, PyStrRef, PyTuple, PyTupleRef, PyType,
         },
         common::{hash::PyHash, str::to_ascii},
         function::{
@@ -29,7 +30,6 @@ mod builtins {
         readline::{Readline, ReadlineResult},
         stdlib::sys,
         types::PyComparisonOp,
-        AsObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
     use num_traits::{Signed, ToPrimitive};
 
@@ -157,8 +157,7 @@ mod builtins {
 
             #[cfg(not(feature = "rustpython-parser"))]
             {
-                const PARSER_NOT_SUPPORTED: &str =
-        "can't compile() source code when the `parser` feature of rustpython is disabled";
+                const PARSER_NOT_SUPPORTED: &str = "can't compile() source code when the `parser` feature of rustpython is disabled";
                 Err(vm.new_type_error(PARSER_NOT_SUPPORTED.to_owned()))
             }
             #[cfg(feature = "rustpython-parser")]
@@ -535,7 +534,7 @@ mod builtins {
             None => {
                 return default.ok_or_else(|| {
                     vm.new_value_error(format!("{func_name}() arg is an empty sequence"))
-                })
+                });
             }
         };
 
diff --git a/vm/src/stdlib/codecs.rs b/vm/src/stdlib/codecs.rs
index 71317bf484..976545f64b 100644
--- a/vm/src/stdlib/codecs.rs
+++ b/vm/src/stdlib/codecs.rs
@@ -4,10 +4,10 @@ pub(crate) use _codecs::make_module;
 mod _codecs {
     use crate::common::encodings;
     use crate::{
+        AsObject, PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyBytes, PyBytesRef, PyStr, PyStrRef, PyTuple},
         codecs,
         function::{ArgBytesLike, FuncArgs},
-        AsObject, PyObject, PyObjectRef, PyResult, TryFromBorrowedObject, VirtualMachine,
     };
     use std::ops::Range;
 
diff --git a/vm/src/stdlib/collections.rs b/vm/src/stdlib/collections.rs
index 5a9a172d53..fc867db2b1 100644
--- a/vm/src/stdlib/collections.rs
+++ b/vm/src/stdlib/collections.rs
@@ -3,6 +3,7 @@ pub(crate) use _collections::make_module;
 #[pymodule]
 mod _collections {
     use crate::{
+        AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         atomic_func,
         builtins::{
             IterStatus::{Active, Exhausted},
@@ -20,7 +21,6 @@ mod _collections {
             Iterable, PyComparisonOp, Representable, SelfIter,
         },
         utils::collection_repr,
-        AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use std::cmp::max;
diff --git a/vm/src/stdlib/ctypes.rs b/vm/src/stdlib/ctypes.rs
new file mode 100644
index 0000000000..2580939b62
--- /dev/null
+++ b/vm/src/stdlib/ctypes.rs
@@ -0,0 +1,226 @@
+pub(crate) mod array;
+pub(crate) mod base;
+pub(crate) mod function;
+pub(crate) mod library;
+pub(crate) mod pointer;
+pub(crate) mod structure;
+pub(crate) mod union;
+
+use crate::builtins::PyModule;
+use crate::class::PyClassImpl;
+use crate::stdlib::ctypes::base::{PyCData, PyCSimple, PySimpleMeta};
+use crate::{Py, PyRef, VirtualMachine};
+
+pub fn extend_module_nodes(vm: &VirtualMachine, module: &Py<PyModule>) {
+    let ctx = &vm.ctx;
+    PySimpleMeta::make_class(ctx);
+    extend_module!(vm, module, {
+        "_CData" => PyCData::make_class(ctx),
+        "_SimpleCData" => PyCSimple::make_class(ctx),
+        "Array" => array::PyCArray::make_class(ctx),
+        "CFuncPtr" => function::PyCFuncPtr::make_class(ctx),
+        "_Pointer" => pointer::PyCPointer::make_class(ctx),
+        "_pointer_type_cache" => ctx.new_dict(),
+        "Structure" => structure::PyCStructure::make_class(ctx),
+        "Union" => union::PyCUnion::make_class(ctx),
+    })
+}
+
+pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
+    let module = _ctypes::make_module(vm);
+    extend_module_nodes(vm, &module);
+    module
+}
+
+#[pymodule]
+pub(crate) mod _ctypes {
+    use super::base::PyCSimple;
+    use crate::builtins::PyTypeRef;
+    use crate::class::StaticType;
+    use crate::function::Either;
+    use crate::stdlib::ctypes::library;
+    use crate::{AsObject, PyObjectRef, PyResult, TryFromObject, VirtualMachine};
+    use crossbeam_utils::atomic::AtomicCell;
+    use std::ffi::{
+        c_double, c_float, c_int, c_long, c_longlong, c_schar, c_short, c_uchar, c_uint, c_ulong,
+        c_ulonglong,
+    };
+    use std::mem;
+    use widestring::WideChar;
+
+    #[pyattr(name = "__version__")]
+    const __VERSION__: &str = "1.1.0";
+
+    // TODO: get properly
+    #[pyattr(name = "RTLD_LOCAL")]
+    const RTLD_LOCAL: i32 = 0;
+
+    // TODO: get properly
+    #[pyattr(name = "RTLD_GLOBAL")]
+    const RTLD_GLOBAL: i32 = 0;
+
+    #[cfg(target_os = "windows")]
+    #[pyattr(name = "SIZEOF_TIME_T")]
+    pub const SIZEOF_TIME_T: usize = 8;
+    #[cfg(not(target_os = "windows"))]
+    #[pyattr(name = "SIZEOF_TIME_T")]
+    pub const SIZEOF_TIME_T: usize = 4;
+
+    #[pyattr(name = "CTYPES_MAX_ARGCOUNT")]
+    pub const CTYPES_MAX_ARGCOUNT: usize = 1024;
+
+    #[pyattr]
+    pub const FUNCFLAG_STDCALL: u32 = 0x0;
+    #[pyattr]
+    pub const FUNCFLAG_CDECL: u32 = 0x1;
+    #[pyattr]
+    pub const FUNCFLAG_HRESULT: u32 = 0x2;
+    #[pyattr]
+    pub const FUNCFLAG_PYTHONAPI: u32 = 0x4;
+    #[pyattr]
+    pub const FUNCFLAG_USE_ERRNO: u32 = 0x8;
+    #[pyattr]
+    pub const FUNCFLAG_USE_LASTERROR: u32 = 0x10;
+
+    #[pyattr]
+    pub const TYPEFLAG_ISPOINTER: u32 = 0x100;
+    #[pyattr]
+    pub const TYPEFLAG_HASPOINTER: u32 = 0x200;
+
+    #[pyattr]
+    pub const DICTFLAG_FINAL: u32 = 0x1000;
+
+    #[pyattr(name = "ArgumentError", once)]
+    fn argument_error(vm: &VirtualMachine) -> PyTypeRef {
+        vm.ctx.new_exception_type(
+            "_ctypes",
+            "ArgumentError",
+            Some(vec![vm.ctx.exceptions.exception_type.to_owned()]),
+        )
+    }
+
+    #[pyattr(name = "FormatError", once)]
+    fn format_error(vm: &VirtualMachine) -> PyTypeRef {
+        vm.ctx.new_exception_type(
+            "_ctypes",
+            "FormatError",
+            Some(vec![vm.ctx.exceptions.exception_type.to_owned()]),
+        )
+    }
+
+    pub fn get_size(ty: &str) -> usize {
+        match ty {
+            "u" => mem::size_of::<WideChar>(),
+            "c" | "b" => mem::size_of::<c_schar>(),
+            "h" => mem::size_of::<c_short>(),
+            "H" => mem::size_of::<c_short>(),
+            "i" => mem::size_of::<c_int>(),
+            "I" => mem::size_of::<c_uint>(),
+            "l" => mem::size_of::<c_long>(),
+            "q" => mem::size_of::<c_longlong>(),
+            "L" => mem::size_of::<c_ulong>(),
+            "Q" => mem::size_of::<c_ulonglong>(),
+            "f" => mem::size_of::<c_float>(),
+            "d" | "g" => mem::size_of::<c_double>(),
+            "?" | "B" => mem::size_of::<c_uchar>(),
+            "P" | "z" | "Z" => mem::size_of::<usize>(),
+            _ => unreachable!(),
+        }
+    }
+
+    const SIMPLE_TYPE_CHARS: &str = "cbBhHiIlLdfguzZPqQ?";
+
+    pub fn new_simple_type(
+        cls: Either<&PyObjectRef, &PyTypeRef>,
+        vm: &VirtualMachine,
+    ) -> PyResult<PyCSimple> {
+        let cls = match cls {
+            Either::A(obj) => obj,
+            Either::B(typ) => typ.as_object(),
+        };
+
+        if let Ok(_type_) = cls.get_attr("_type_", vm) {
+            if _type_.is_instance((&vm.ctx.types.str_type).as_ref(), vm)? {
+                let tp_str = _type_.str(vm)?.to_string();
+
+                if tp_str.len() != 1 {
+                    Err(vm.new_value_error(
+                        format!("class must define a '_type_' attribute which must be a string of length 1, str: {tp_str}"),
+                    ))
+                } else if !SIMPLE_TYPE_CHARS.contains(tp_str.as_str()) {
+                    Err(vm.new_attribute_error(format!("class must define a '_type_' attribute which must be\n a single character string containing one of {SIMPLE_TYPE_CHARS}, currently it is {tp_str}.")))
+                } else {
+                    Ok(PyCSimple {
+                        _type_: tp_str,
+                        value: AtomicCell::new(vm.ctx.none()),
+                    })
+                }
+            } else {
+                Err(vm.new_type_error("class must define a '_type_' string attribute".to_string()))
+            }
+        } else {
+            Err(vm.new_attribute_error("class must define a '_type_' attribute".to_string()))
+        }
+    }
+
+    #[pyfunction(name = "sizeof")]
+    pub fn size_of(tp: Either<PyTypeRef, PyObjectRef>, vm: &VirtualMachine) -> PyResult<usize> {
+        match tp {
+            Either::A(type_) if type_.fast_issubclass(PyCSimple::static_type()) => {
+                let zelf = new_simple_type(Either::B(&type_), vm)?;
+                Ok(get_size(zelf._type_.as_str()))
+            }
+            Either::B(obj) if obj.has_attr("size_of_instances", vm)? => {
+                let size_of_method = obj.get_attr("size_of_instances", vm)?;
+                let size_of_return = size_of_method.call(vec![], vm)?;
+                Ok(usize::try_from_object(vm, size_of_return)?)
+            }
+            _ => Err(vm.new_type_error("this type has no size".to_string())),
+        }
+    }
+
+    #[pyfunction(name = "LoadLibrary")]
+    fn load_library(name: String, vm: &VirtualMachine) -> PyResult<usize> {
+        // TODO: audit functions first
+        let cache = library::libcache();
+        let mut cache_write = cache.write();
+        let lib_ref = cache_write.get_or_insert_lib(&name, vm).unwrap();
+        Ok(lib_ref.get_pointer())
+    }
+
+    #[pyfunction(name = "FreeLibrary")]
+    fn free_library(handle: usize) -> PyResult<()> {
+        let cache = library::libcache();
+        let mut cache_write = cache.write();
+        cache_write.drop_lib(handle);
+        Ok(())
+    }
+
+    #[pyfunction(name = "POINTER")]
+    pub fn pointer(_cls: PyTypeRef) {}
+
+    #[pyfunction]
+    pub fn pointer_fn(_inst: PyObjectRef) {}
+
+    #[cfg(target_os = "windows")]
+    #[pyfunction(name = "_check_HRESULT")]
+    pub fn check_hresult(_self: PyObjectRef, hr: i32, _vm: &VirtualMachine) -> PyResult<i32> {
+        // TODO: fixme
+        if hr < 0 {
+            // vm.ctx.new_windows_error(hr)
+            todo!();
+        } else {
+            Ok(hr)
+        }
+    }
+
+    #[pyfunction]
+    fn get_errno() -> i32 {
+        errno::errno().0
+    }
+
+    #[pyfunction]
+    fn set_errno(value: i32) {
+        errno::set_errno(errno::Errno(value));
+    }
+}
diff --git a/vm/src/stdlib/ctypes/array.rs b/vm/src/stdlib/ctypes/array.rs
new file mode 100644
index 0000000000..8b023582c9
--- /dev/null
+++ b/vm/src/stdlib/ctypes/array.rs
@@ -0,0 +1,5 @@
+#[pyclass(name = "Array", module = "_ctypes")]
+pub struct PyCArray {}
+
+#[pyclass(flags(BASETYPE, IMMUTABLETYPE))]
+impl PyCArray {}
diff --git a/vm/src/stdlib/ctypes/base.rs b/vm/src/stdlib/ctypes/base.rs
new file mode 100644
index 0000000000..a4147c62b2
--- /dev/null
+++ b/vm/src/stdlib/ctypes/base.rs
@@ -0,0 +1,224 @@
+use crate::builtins::PyType;
+use crate::builtins::{PyBytes, PyFloat, PyInt, PyNone, PyStr, PyTypeRef};
+use crate::convert::ToPyObject;
+use crate::function::{Either, OptionalArg};
+use crate::stdlib::ctypes::_ctypes::new_simple_type;
+use crate::types::Constructor;
+use crate::{AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine};
+use crossbeam_utils::atomic::AtomicCell;
+use num_traits::ToPrimitive;
+use rustpython_common::lock::PyRwLock;
+use std::fmt::Debug;
+
+#[allow(dead_code)]
+fn set_primitive(_type_: &str, value: &PyObjectRef, vm: &VirtualMachine) -> PyResult {
+    match _type_ {
+        "c" => {
+            if value
+                .clone()
+                .downcast_exact::<PyBytes>(vm)
+                .is_ok_and(|v| v.len() == 1)
+                || value
+                    .clone()
+                    .downcast_exact::<PyBytes>(vm)
+                    .is_ok_and(|v| v.len() == 1)
+                || value
+                    .clone()
+                    .downcast_exact::<PyInt>(vm)
+                    .map_or(Ok(false), |v| {
+                        let n = v.as_bigint().to_i64();
+                        if let Some(n) = n {
+                            Ok((0..=255).contains(&n))
+                        } else {
+                            Ok(false)
+                        }
+                    })?
+            {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error(
+                    "one character bytes, bytearray or integer expected".to_string(),
+                ))
+            }
+        }
+        "u" => {
+            if let Ok(b) = value.str(vm).map(|v| v.to_string().chars().count() == 1) {
+                if b {
+                    Ok(value.clone())
+                } else {
+                    Err(vm.new_type_error("one character unicode string expected".to_string()))
+                }
+            } else {
+                Err(vm.new_type_error(format!(
+                    "unicode string expected instead of {} instance",
+                    value.class().name()
+                )))
+            }
+        }
+        "b" | "h" | "H" | "i" | "I" | "l" | "q" | "L" | "Q" => {
+            if value.clone().downcast_exact::<PyInt>(vm).is_ok() {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error(format!(
+                    "an integer is required (got type {})",
+                    value.class().name()
+                )))
+            }
+        }
+        "f" | "d" | "g" => {
+            if value.clone().downcast_exact::<PyFloat>(vm).is_ok() {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error(format!("must be real number, not {}", value.class().name())))
+            }
+        }
+        "?" => Ok(PyObjectRef::from(
+            vm.ctx.new_bool(value.clone().try_to_bool(vm)?),
+        )),
+        "B" => {
+            if value.clone().downcast_exact::<PyInt>(vm).is_ok() {
+                Ok(vm.new_pyobj(u8::try_from_object(vm, value.clone())?))
+            } else {
+                Err(vm.new_type_error(format!("int expected instead of {}", value.class().name())))
+            }
+        }
+        "z" => {
+            if value.clone().downcast_exact::<PyInt>(vm).is_ok()
+                || value.clone().downcast_exact::<PyBytes>(vm).is_ok()
+            {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error(format!(
+                    "bytes or integer address expected instead of {} instance",
+                    value.class().name()
+                )))
+            }
+        }
+        "Z" => {
+            if value.clone().downcast_exact::<PyStr>(vm).is_ok() {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error(format!(
+                    "unicode string or integer address expected instead of {} instance",
+                    value.class().name()
+                )))
+            }
+        }
+        _ => {
+            // "P"
+            if value.clone().downcast_exact::<PyInt>(vm).is_ok()
+                || value.clone().downcast_exact::<PyNone>(vm).is_ok()
+            {
+                Ok(value.clone())
+            } else {
+                Err(vm.new_type_error("cannot be converted to pointer".to_string()))
+            }
+        }
+    }
+}
+
+pub struct RawBuffer {
+    #[allow(dead_code)]
+    pub inner: Box<[u8]>,
+    #[allow(dead_code)]
+    pub size: usize,
+}
+
+#[pyclass(name = "_CData", module = "_ctypes")]
+pub struct PyCData {
+    _objects: AtomicCell<Vec<PyObjectRef>>,
+    _buffer: PyRwLock<RawBuffer>,
+}
+
+#[pyclass]
+impl PyCData {}
+
+#[pyclass(module = "_ctypes", name = "PyCSimpleType", base = "PyType")]
+pub struct PySimpleMeta {}
+
+#[pyclass(flags(BASETYPE))]
+impl PySimpleMeta {
+    #[allow(clippy::new_ret_no_self)]
+    #[pymethod]
+    fn new(cls: PyTypeRef, _: OptionalArg, vm: &VirtualMachine) -> PyResult {
+        Ok(PyObjectRef::from(
+            new_simple_type(Either::B(&cls), vm)?
+                .into_ref_with_type(vm, cls)?
+                .clone(),
+        ))
+    }
+}
+
+#[pyclass(
+    name = "_SimpleCData",
+    base = "PyCData",
+    module = "_ctypes",
+    metaclass = "PySimpleMeta"
+)]
+#[derive(PyPayload)]
+pub struct PyCSimple {
+    pub _type_: String,
+    pub value: AtomicCell<PyObjectRef>,
+}
+
+impl Debug for PyCSimple {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("PyCSimple")
+            .field("_type_", &self._type_)
+            .finish()
+    }
+}
+
+impl Constructor for PyCSimple {
+    type Args = (OptionalArg,);
+
+    fn py_new(cls: PyTypeRef, args: Self::Args, vm: &VirtualMachine) -> PyResult {
+        let attributes = cls.get_attributes();
+        let _type_ = attributes
+            .iter()
+            .find(|(k, _)| k.to_object().str(vm).unwrap().to_string() == *"_type_")
+            .unwrap()
+            .1
+            .str(vm)?
+            .to_string();
+        let value = if let Some(ref v) = args.0.into_option() {
+            set_primitive(_type_.as_str(), v, vm)?
+        } else {
+            match _type_.as_str() {
+                "c" | "u" => PyObjectRef::from(vm.ctx.new_bytes(vec![0])),
+                "b" | "B" | "h" | "H" | "i" | "I" | "l" | "q" | "L" | "Q" => {
+                    PyObjectRef::from(vm.ctx.new_int(0))
+                }
+                "f" | "d" | "g" => PyObjectRef::from(vm.ctx.new_float(0.0)),
+                "?" => PyObjectRef::from(vm.ctx.new_bool(false)),
+                _ => vm.ctx.none(), // "z" | "Z" | "P"
+            }
+        };
+        Ok(PyCSimple {
+            _type_,
+            value: AtomicCell::new(value),
+        }
+        .to_pyobject(vm))
+    }
+}
+
+#[pyclass(flags(BASETYPE), with(Constructor))]
+impl PyCSimple {
+    #[pygetset(name = "value")]
+    pub fn value(instance: PyObjectRef, vm: &VirtualMachine) -> PyResult<PyObjectRef> {
+        let zelf: &Py<Self> = instance
+            .downcast_ref()
+            .ok_or_else(|| vm.new_type_error("cannot get value of instance".to_string()))?;
+        Ok(unsafe { (*zelf.value.as_ptr()).clone() })
+    }
+
+    #[pygetset(name = "value", setter)]
+    fn set_value(instance: PyObjectRef, value: PyObjectRef, vm: &VirtualMachine) -> PyResult<()> {
+        let zelf: PyRef<Self> = instance
+            .downcast()
+            .map_err(|_| vm.new_type_error("cannot set value of instance".to_string()))?;
+        let content = set_primitive(zelf._type_.as_str(), &value, vm)?;
+        zelf.value.store(content);
+        Ok(())
+    }
+}
diff --git a/vm/src/stdlib/ctypes/function.rs b/vm/src/stdlib/ctypes/function.rs
new file mode 100644
index 0000000000..a7ee07744b
--- /dev/null
+++ b/vm/src/stdlib/ctypes/function.rs
@@ -0,0 +1,24 @@
+use crate::PyObjectRef;
+use crate::stdlib::ctypes::PyCData;
+use crossbeam_utils::atomic::AtomicCell;
+use rustpython_common::lock::PyRwLock;
+use std::ffi::c_void;
+
+#[derive(Debug)]
+pub struct Function {
+    _pointer: *mut c_void,
+    _arguments: Vec<()>,
+    _return_type: Box<()>,
+}
+
+#[pyclass(module = "_ctypes", name = "CFuncPtr", base = "PyCData")]
+pub struct PyCFuncPtr {
+    pub _name_: String,
+    pub _argtypes_: AtomicCell<Vec<PyObjectRef>>,
+    pub _restype_: AtomicCell<PyObjectRef>,
+    _handle: PyObjectRef,
+    _f: PyRwLock<Function>,
+}
+
+#[pyclass]
+impl PyCFuncPtr {}
diff --git a/vm/src/stdlib/ctypes/library.rs b/vm/src/stdlib/ctypes/library.rs
new file mode 100644
index 0000000000..94b6327440
--- /dev/null
+++ b/vm/src/stdlib/ctypes/library.rs
@@ -0,0 +1,115 @@
+use crate::VirtualMachine;
+use crossbeam_utils::atomic::AtomicCell;
+use libloading::Library;
+use rustpython_common::lock::PyRwLock;
+use std::collections::HashMap;
+use std::ffi::c_void;
+use std::fmt;
+use std::ptr::null;
+
+pub struct SharedLibrary {
+    lib: AtomicCell<Option<Library>>,
+}
+
+impl fmt::Debug for SharedLibrary {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "SharedLibrary")
+    }
+}
+
+impl SharedLibrary {
+    pub fn new(name: &str) -> Result<SharedLibrary, libloading::Error> {
+        Ok(SharedLibrary {
+            lib: AtomicCell::new(Some(unsafe { Library::new(name)? })),
+        })
+    }
+
+    #[allow(dead_code)]
+    pub fn get_sym(&self, name: &str) -> Result<*mut c_void, String> {
+        if let Some(inner) = unsafe { &*self.lib.as_ptr() } {
+            unsafe {
+                inner
+                    .get(name.as_bytes())
+                    .map(|f: libloading::Symbol<*mut c_void>| *f)
+                    .map_err(|err| err.to_string())
+            }
+        } else {
+            Err("The library has been closed".to_string())
+        }
+    }
+
+    pub fn get_pointer(&self) -> usize {
+        if let Some(l) = unsafe { &*self.lib.as_ptr() } {
+            l as *const Library as usize
+        } else {
+            null::<c_void>() as usize
+        }
+    }
+
+    pub fn is_closed(&self) -> bool {
+        unsafe { &*self.lib.as_ptr() }.is_none()
+    }
+
+    pub fn close(&self) {
+        let old = self.lib.take();
+        self.lib.store(None);
+        drop(old);
+    }
+}
+
+impl Drop for SharedLibrary {
+    fn drop(&mut self) {
+        self.close();
+    }
+}
+
+pub struct ExternalLibs {
+    libraries: HashMap<usize, SharedLibrary>,
+}
+
+impl ExternalLibs {
+    pub fn new() -> Self {
+        Self {
+            libraries: HashMap::new(),
+        }
+    }
+
+    #[allow(dead_code)]
+    pub fn get_lib(&self, key: usize) -> Option<&SharedLibrary> {
+        self.libraries.get(&key)
+    }
+
+    pub fn get_or_insert_lib(
+        &mut self,
+        library_path: &str,
+        _vm: &VirtualMachine,
+    ) -> Result<&SharedLibrary, libloading::Error> {
+        let nlib = SharedLibrary::new(library_path)?;
+        let key = nlib.get_pointer();
+
+        match self.libraries.get(&key) {
+            Some(l) => {
+                if l.is_closed() {
+                    self.libraries.insert(key, nlib);
+                }
+            }
+            _ => {
+                self.libraries.insert(key, nlib);
+            }
+        };
+
+        Ok(self.libraries.get(&key).unwrap())
+    }
+
+    pub fn drop_lib(&mut self, key: usize) {
+        self.libraries.remove(&key);
+    }
+}
+
+rustpython_common::static_cell! {
+    static LIBCACHE: PyRwLock<ExternalLibs>;
+}
+
+pub fn libcache() -> &'static PyRwLock<ExternalLibs> {
+    LIBCACHE.get_or_init(|| PyRwLock::new(ExternalLibs::new()))
+}
diff --git a/vm/src/stdlib/ctypes/pointer.rs b/vm/src/stdlib/ctypes/pointer.rs
new file mode 100644
index 0000000000..d1360f9862
--- /dev/null
+++ b/vm/src/stdlib/ctypes/pointer.rs
@@ -0,0 +1,5 @@
+#[pyclass(name = "Pointer", module = "_ctypes")]
+pub struct PyCPointer {}
+
+#[pyclass(flags(BASETYPE, IMMUTABLETYPE))]
+impl PyCPointer {}
diff --git a/vm/src/stdlib/ctypes/structure.rs b/vm/src/stdlib/ctypes/structure.rs
new file mode 100644
index 0000000000..13cca6c260
--- /dev/null
+++ b/vm/src/stdlib/ctypes/structure.rs
@@ -0,0 +1,5 @@
+#[pyclass(name = "Structure", module = "_ctypes")]
+pub struct PyCStructure {}
+
+#[pyclass(flags(BASETYPE, IMMUTABLETYPE))]
+impl PyCStructure {}
diff --git a/vm/src/stdlib/ctypes/union.rs b/vm/src/stdlib/ctypes/union.rs
new file mode 100644
index 0000000000..5a39d9062e
--- /dev/null
+++ b/vm/src/stdlib/ctypes/union.rs
@@ -0,0 +1,5 @@
+#[pyclass(name = "Union", module = "_ctypes")]
+pub struct PyCUnion {}
+
+#[pyclass(flags(BASETYPE, IMMUTABLETYPE))]
+impl PyCUnion {}
diff --git a/vm/src/stdlib/errno.rs b/vm/src/stdlib/errno.rs
index a142d68a34..247e2a2340 100644
--- a/vm/src/stdlib/errno.rs
+++ b/vm/src/stdlib/errno.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 #[pymodule]
 mod errno {}
@@ -38,9 +38,9 @@ pub mod errors {
             WSAEPROVIDERFAILEDINIT, WSAEREFUSED, WSAEREMOTE, WSAESHUTDOWN, WSAESOCKTNOSUPPORT,
             WSAESTALE, WSAETIMEDOUT, WSAETOOMANYREFS, WSAEUSERS, WSAEWOULDBLOCK, WSAHOST_NOT_FOUND,
             WSAID_ACCEPTEX, WSAID_CONNECTEX, WSAID_DISCONNECTEX, WSAID_GETACCEPTEXSOCKADDRS,
-            WSAID_TRANSMITFILE, WSAID_TRANSMITPACKETS, WSAID_WSAPOLL, WSAID_WSARECVMSG,
-            WSANOTINITIALISED, WSANO_DATA, WSANO_RECOVERY, WSAPROTOCOL_LEN, WSASERVICE_NOT_FOUND,
-            WSASYSCALLFAILURE, WSASYSNOTREADY, WSASYS_STATUS_LEN, WSATRY_AGAIN, WSATYPE_NOT_FOUND,
+            WSAID_TRANSMITFILE, WSAID_TRANSMITPACKETS, WSAID_WSAPOLL, WSAID_WSARECVMSG, WSANO_DATA,
+            WSANO_RECOVERY, WSANOTINITIALISED, WSAPROTOCOL_LEN, WSASERVICE_NOT_FOUND,
+            WSASYS_STATUS_LEN, WSASYSCALLFAILURE, WSASYSNOTREADY, WSATRY_AGAIN, WSATYPE_NOT_FOUND,
             WSAVERNOTSUPPORTED,
         },
     };
diff --git a/vm/src/stdlib/functools.rs b/vm/src/stdlib/functools.rs
index d13b9b84f6..145d95d6ff 100644
--- a/vm/src/stdlib/functools.rs
+++ b/vm/src/stdlib/functools.rs
@@ -2,7 +2,7 @@ pub(crate) use _functools::make_module;
 
 #[pymodule]
 mod _functools {
-    use crate::{function::OptionalArg, protocol::PyIter, PyObjectRef, PyResult, VirtualMachine};
+    use crate::{PyObjectRef, PyResult, VirtualMachine, function::OptionalArg, protocol::PyIter};
 
     #[pyfunction]
     fn reduce(
diff --git a/vm/src/stdlib/imp.rs b/vm/src/stdlib/imp.rs
index d8727e74ff..5c3f4bf61d 100644
--- a/vm/src/stdlib/imp.rs
+++ b/vm/src/stdlib/imp.rs
@@ -1,11 +1,11 @@
 use crate::frozen::FrozenModule;
-use crate::{builtins::PyBaseExceptionRef, VirtualMachine};
+use crate::{VirtualMachine, builtins::PyBaseExceptionRef};
 pub(crate) use _imp::make_module;
 
 #[cfg(feature = "threading")]
 #[pymodule(sub)]
 mod lock {
-    use crate::{stdlib::thread::RawRMutex, PyResult, VirtualMachine};
+    use crate::{PyResult, VirtualMachine, stdlib::thread::RawRMutex};
 
     static IMP_LOCK: RawRMutex = RawRMutex::INIT;
 
@@ -60,7 +60,9 @@ impl FrozenError {
         use FrozenError::*;
         let msg = match self {
             BadName | NotFound => format!("No such frozen object named {mod_name}"),
-            Disabled => format!("Frozen modules are disabled and the frozen object named {mod_name} is not essential"),
+            Disabled => format!(
+                "Frozen modules are disabled and the frozen object named {mod_name} is not essential"
+            ),
             Excluded => format!("Excluded frozen object named {mod_name}"),
             Invalid => format!("Frozen object named {mod_name} is invalid"),
         };
@@ -80,9 +82,10 @@ fn find_frozen(name: &str, vm: &VirtualMachine) -> Result<FrozenModule, FrozenEr
 #[pymodule(with(lock))]
 mod _imp {
     use crate::{
+        PyObjectRef, PyRef, PyResult, VirtualMachine,
         builtins::{PyBytesRef, PyCode, PyMemoryView, PyModule, PyStrRef},
         function::OptionalArg,
-        import, PyObjectRef, PyRef, PyResult, VirtualMachine,
+        import,
     };
 
     #[pyattr]
diff --git a/vm/src/stdlib/io.rs b/vm/src/stdlib/io.rs
index 3c35b05e1a..1b5eb6d60c 100644
--- a/vm/src/stdlib/io.rs
+++ b/vm/src/stdlib/io.rs
@@ -10,12 +10,12 @@ cfg_if::cfg_if! {
 }
 
 use crate::{
+    PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyModule},
     common::os::ErrorExt,
     convert::{IntoPyException, ToPyException},
-    PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
-pub use _io::{io_open as open, OpenArgs};
+pub use _io::{OpenArgs, io_open as open};
 
 impl ToPyException for std::io::Error {
     fn to_pyexception(&self, vm: &VirtualMachine) -> PyBaseExceptionRef {
@@ -118,6 +118,8 @@ impl std::os::fd::AsRawFd for Fildes {
 mod _io {
     use super::*;
     use crate::{
+        AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
+        TryFromBorrowedObject, TryFromObject,
         builtins::{
             PyBaseExceptionRef, PyByteArray, PyBytes, PyBytesRef, PyIntRef, PyMemoryView, PyStr,
             PyStrRef, PyTuple, PyTupleRef, PyType, PyTypeRef,
@@ -140,8 +142,6 @@ mod _io {
             Callable, Constructor, DefaultConstructor, Destructor, Initializer, IterNext, Iterable,
         },
         vm::VirtualMachine,
-        AsObject, Context, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
-        TryFromBorrowedObject, TryFromObject,
     };
     use bstr::ByteSlice;
     use crossbeam_utils::atomic::AtomicCell;
@@ -149,7 +149,7 @@ mod _io {
     use num_traits::ToPrimitive;
     use std::{
         borrow::Cow,
-        io::{self, prelude::*, Cursor, SeekFrom},
+        io::{self, Cursor, SeekFrom, prelude::*},
         ops::Range,
     };
 
@@ -319,11 +319,7 @@ mod _io {
                 // For Cursor, fill_buf returns all of the remaining data unlike other BufReads which have outer reading source.
                 // Unless we add other data by write, there will be no more data.
                 let buf = self.cursor.fill_buf().map_err(|err| os_err(vm, err))?;
-                if size < buf.len() {
-                    &buf[..size]
-                } else {
-                    buf
-                }
+                if size < buf.len() { &buf[..size] } else { buf }
             };
             let buf = match available.find_byte(byte) {
                 Some(i) => available[..=i].to_vec(),
@@ -482,7 +478,7 @@ mod _io {
             let size = size.to_usize();
             let read = instance.get_attr("read", vm)?;
             let mut res = Vec::new();
-            while size.map_or(true, |s| res.len() < s) {
+            while size.is_none_or(|s| res.len() < s) {
                 let read_res = ArgBytesLike::try_from_object(vm, read.call((1,), vm)?)?;
                 if read_res.with_ref(|b| b.is_empty()) {
                     break;
@@ -2496,7 +2492,7 @@ mod _io {
                 _ => {
                     return Err(
                         vm.new_value_error(format!("invalid whence ({how}, should be 0, 1 or 2)"))
-                    )
+                    );
                 }
             };
             use crate::types::PyComparisonOp;
@@ -3006,7 +3002,7 @@ mod _io {
     }
 
     fn parse_decoder_state(state: PyObjectRef, vm: &VirtualMachine) -> PyResult<(PyBytesRef, i32)> {
-        use crate::builtins::{int, PyTuple};
+        use crate::builtins::{PyTuple, int};
         let state_err = || vm.new_type_error("illegal decoder state".to_owned());
         let state = state.downcast::<PyTuple>().map_err(|_| state_err())?;
         match state.as_slice() {
@@ -4032,8 +4028,9 @@ mod _io {
 #[cfg(any(not(target_arch = "wasm32"), target_os = "wasi"))]
 #[pymodule]
 mod fileio {
-    use super::{Offset, _io::*};
+    use super::{_io::*, Offset};
     use crate::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyStr, PyStrRef},
         common::crt_fd::Fd,
         convert::ToPyException,
@@ -4041,7 +4038,6 @@ mod fileio {
         ospath::{IOErrorBuilder, OsPath, OsPathOrFd},
         stdlib::os,
         types::{Constructor, DefaultConstructor, Initializer, Representable},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use std::io::{Read, Write};
diff --git a/vm/src/stdlib/itertools.rs b/vm/src/stdlib/itertools.rs
index eb800a0b1f..65c1482057 100644
--- a/vm/src/stdlib/itertools.rs
+++ b/vm/src/stdlib/itertools.rs
@@ -4,9 +4,11 @@ pub(crate) use decl::make_module;
 mod decl {
     use crate::stdlib::itertools::decl::int::get_value;
     use crate::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, PyWeakRef, TryFromObject,
+        VirtualMachine,
         builtins::{
-            int, tuple::IntoPyTuple, PyGenericAlias, PyInt, PyIntRef, PyList, PyTuple, PyTupleRef,
-            PyTypeRef,
+            PyGenericAlias, PyInt, PyIntRef, PyList, PyTuple, PyTupleRef, PyTypeRef, int,
+            tuple::IntoPyTuple,
         },
         common::{
             lock::{PyMutex, PyRwLock, PyRwLockWriteGuard},
@@ -18,8 +20,6 @@ mod decl {
         protocol::{PyIter, PyIterReturn, PyNumber},
         stdlib::sys,
         types::{Constructor, IterNext, Iterable, Representable, SelfIter},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, PyWeakRef, TryFromObject,
-        VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use malachite_bigint::BigInt;
diff --git a/vm/src/stdlib/marshal.rs b/vm/src/stdlib/marshal.rs
index 35f9b93d5f..fd7332e7c2 100644
--- a/vm/src/stdlib/marshal.rs
+++ b/vm/src/stdlib/marshal.rs
@@ -5,6 +5,7 @@ mod decl {
     use crate::builtins::code::{CodeObject, Literal, PyObjBag};
     use crate::class::StaticType;
     use crate::{
+        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{
             PyBool, PyByteArray, PyBytes, PyCode, PyComplex, PyDict, PyEllipsis, PyFloat,
             PyFrozenSet, PyInt, PyList, PyNone, PySet, PyStopIteration, PyStr, PyTuple,
@@ -13,7 +14,6 @@ mod decl {
         function::{ArgBytesLike, OptionalArg},
         object::AsObject,
         protocol::PyBuffer,
-        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     };
     use malachite_bigint::BigInt;
     use num_complex::Complex64;
diff --git a/vm/src/stdlib/mod.rs b/vm/src/stdlib/mod.rs
index 12baee11f7..529a40e861 100644
--- a/vm/src/stdlib/mod.rs
+++ b/vm/src/stdlib/mod.rs
@@ -37,6 +37,8 @@ pub mod posix;
 #[path = "posix_compat.rs"]
 pub mod posix;
 
+#[cfg(any(target_family = "unix", target_family = "windows"))]
+mod ctypes;
 #[cfg(windows)]
 pub(crate) mod msvcrt;
 #[cfg(all(unix, not(any(target_os = "android", target_os = "redox"))))]
@@ -48,7 +50,7 @@ mod winapi;
 #[cfg(windows)]
 mod winreg;
 
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 use std::{borrow::Cow, collections::HashMap};
 
 pub type StdlibInitFunc = Box<py_dyn_fn!(dyn Fn(&VirtualMachine) -> PyRef<PyModule>)>;
@@ -124,5 +126,9 @@ pub fn get_module_inits() -> StdlibMap {
             "_winapi" => winapi::make_module,
             "winreg" => winreg::make_module,
         }
+        #[cfg(any(target_family = "unix", target_family = "windows"))]
+        {
+            "_ctypes" => ctypes::make_module,
+        }
     }
 }
diff --git a/vm/src/stdlib/msvcrt.rs b/vm/src/stdlib/msvcrt.rs
index 03ddb44f22..7b3620ad51 100644
--- a/vm/src/stdlib/msvcrt.rs
+++ b/vm/src/stdlib/msvcrt.rs
@@ -3,10 +3,10 @@ pub use msvcrt::*;
 #[pymodule]
 mod msvcrt {
     use crate::{
+        PyRef, PyResult, VirtualMachine,
         builtins::{PyBytes, PyStrRef},
         common::suppress_iph,
         stdlib::os::errno_err,
-        PyRef, PyResult, VirtualMachine,
     };
     use itertools::Itertools;
     use windows_sys::Win32::{
@@ -24,7 +24,7 @@ mod msvcrt {
         unsafe { suppress_iph!(_setmode(fd, libc::O_BINARY)) };
     }
 
-    extern "C" {
+    unsafe extern "C" {
         fn _getch() -> i32;
         fn _getwch() -> u32;
         fn _getche() -> i32;
@@ -70,7 +70,7 @@ mod msvcrt {
         Ok(())
     }
 
-    extern "C" {
+    unsafe extern "C" {
         fn _setmode(fd: i32, flags: i32) -> i32;
     }
 
@@ -84,7 +84,7 @@ mod msvcrt {
         }
     }
 
-    extern "C" {
+    unsafe extern "C" {
         fn _open_osfhandle(osfhandle: isize, flags: i32) -> i32;
         fn _get_osfhandle(fd: i32) -> libc::intptr_t;
     }
diff --git a/vm/src/stdlib/nt.rs b/vm/src/stdlib/nt.rs
index 803cade630..34fa8792d5 100644
--- a/vm/src/stdlib/nt.rs
+++ b/vm/src/stdlib/nt.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub use module::raw_set_handle_inheritable;
 
@@ -11,13 +11,13 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 #[pymodule(name = "nt", with(super::os::_os))]
 pub(crate) mod module {
     use crate::{
+        PyResult, TryFromObject, VirtualMachine,
         builtins::{PyDictRef, PyListRef, PyStrRef, PyTupleRef},
         common::{crt_fd::Fd, os::last_os_error, suppress_iph},
         convert::ToPyException,
         function::{Either, OptionalArg},
         ospath::OsPath,
-        stdlib::os::{errno_err, DirFd, FollowSymlinks, SupportFunc, TargetIsDirectory, _os},
-        PyResult, TryFromObject, VirtualMachine,
+        stdlib::os::{_os, DirFd, FollowSymlinks, SupportFunc, TargetIsDirectory, errno_err},
     };
     use libc::intptr_t;
     use std::{
@@ -43,6 +43,12 @@ pub(crate) mod module {
                 || attr & FileSystem::FILE_ATTRIBUTE_DIRECTORY != 0))
     }
 
+    #[pyfunction]
+    pub(super) fn _supports_virtual_terminal() -> PyResult<bool> {
+        // TODO: implement this
+        Ok(true)
+    }
+
     #[derive(FromArgs)]
     pub(super) struct SymlinkArgs {
         src: OsPath,
@@ -110,7 +116,7 @@ pub(crate) mod module {
 
     // cwait is available on MSVC only (according to CPython)
     #[cfg(target_env = "msvc")]
-    extern "C" {
+    unsafe extern "C" {
         fn _cwait(termstat: *mut i32, procHandle: intptr_t, action: i32) -> intptr_t;
     }
 
@@ -188,7 +194,7 @@ pub(crate) mod module {
     }
 
     #[cfg(target_env = "msvc")]
-    extern "C" {
+    unsafe extern "C" {
         fn _wexecv(cmdname: *const u16, argv: *const *const u16) -> intptr_t;
     }
 
diff --git a/vm/src/stdlib/operator.rs b/vm/src/stdlib/operator.rs
index 19c1f4b61b..d1a4b376e8 100644
--- a/vm/src/stdlib/operator.rs
+++ b/vm/src/stdlib/operator.rs
@@ -4,6 +4,7 @@ pub(crate) use _operator::make_module;
 mod _operator {
     use crate::common::cmp;
     use crate::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         builtins::{PyInt, PyIntRef, PyStr, PyStrRef, PyTupleRef, PyTypeRef},
         function::Either,
         function::{ArgBytesLike, FuncArgs, KwArgs, OptionalArg},
@@ -11,7 +12,6 @@ mod _operator {
         protocol::PyIter,
         recursion::ReprGuard,
         types::{Callable, Constructor, PyComparisonOp, Representable},
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     };
 
     #[pyfunction]
@@ -336,7 +336,7 @@ mod _operator {
             _ => {
                 return Err(vm.new_type_error(
                     "unsupported operand types(s) or combination of types".to_owned(),
-                ))
+                ));
             }
         };
         Ok(res)
diff --git a/vm/src/stdlib/os.rs b/vm/src/stdlib/os.rs
index 0b3f617552..39701cb3a3 100644
--- a/vm/src/stdlib/os.rs
+++ b/vm/src/stdlib/os.rs
@@ -1,9 +1,9 @@
 use crate::{
+    AsObject, Py, PyPayload, PyResult, VirtualMachine,
     builtins::{PyBaseExceptionRef, PyModule, PySet},
     common::crt_fd::Fd,
     convert::ToPyException,
     function::{ArgumentError, FromArgs, FuncArgs},
-    AsObject, Py, PyPayload, PyResult, VirtualMachine,
 };
 use std::{ffi, fs, io, path::Path};
 
@@ -125,8 +125,9 @@ fn bytes_as_osstr<'a>(b: &'a [u8], vm: &VirtualMachine) -> PyResult<&'a ffi::OsS
 
 #[pymodule(sub)]
 pub(super) mod _os {
-    use super::{errno_err, DirFd, FollowSymlinks, SupportFunc};
+    use super::{DirFd, FollowSymlinks, SupportFunc, errno_err};
     use crate::{
+        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
         builtins::{
             PyBytesRef, PyGenericAlias, PyIntRef, PyStrRef, PyTuple, PyTupleRef, PyTypeRef,
         },
@@ -144,7 +145,6 @@ pub(super) mod _os {
         types::{IterNext, Iterable, PyStructSequence, Representable, SelfIter},
         utils::ToCString,
         vm::VirtualMachine,
-        AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use itertools::Itertools;
@@ -303,11 +303,7 @@ pub(super) mod _os {
         #[cfg(target_os = "redox")]
         let [] = dir_fd.0;
         let res = unsafe { libc::mkdir(path.as_ptr(), mode as _) };
-        if res < 0 {
-            Err(errno_err(vm))
-        } else {
-            Ok(())
-        }
+        if res < 0 { Err(errno_err(vm)) } else { Ok(()) }
     }
 
     #[pyfunction]
@@ -380,8 +376,8 @@ pub(super) mod _os {
 
     fn env_bytes_as_bytes(obj: &Either<PyStrRef, PyBytesRef>) -> &[u8] {
         match obj {
-            Either::A(ref s) => s.as_str().as_bytes(),
-            Either::B(ref b) => b.as_bytes(),
+            Either::A(s) => s.as_str().as_bytes(),
+            Either::B(b) => b.as_bytes(),
         }
     }
 
@@ -401,7 +397,8 @@ pub(super) mod _os {
         }
         let key = super::bytes_as_osstr(key, vm)?;
         let value = super::bytes_as_osstr(value, vm)?;
-        env::set_var(key, value);
+        // SAFETY: requirements forwarded from the caller
+        unsafe { env::set_var(key, value) };
         Ok(())
     }
 
@@ -421,7 +418,8 @@ pub(super) mod _os {
             ));
         }
         let key = super::bytes_as_osstr(key, vm)?;
-        env::remove_var(key);
+        // SAFETY: requirements forwarded from the caller
+        unsafe { env::remove_var(key) };
         Ok(())
     }
 
@@ -966,7 +964,7 @@ pub(super) mod _os {
 
     #[pyfunction]
     fn abort() {
-        extern "C" {
+        unsafe extern "C" {
             fn abort();
         }
         unsafe { abort() }
@@ -978,10 +976,7 @@ pub(super) mod _os {
             return Err(vm.new_value_error("negative argument not allowed".to_owned()));
         }
         let mut buf = vec![0u8; size as usize];
-        getrandom::getrandom(&mut buf).map_err(|e| match e.raw_os_error() {
-            Some(errno) => io::Error::from_raw_os_error(errno).into_pyexception(vm),
-            None => vm.new_os_error("Getting random failed".to_owned()),
-        })?;
+        getrandom::fill(&mut buf).map_err(|e| io::Error::from(e).into_pyexception(vm))?;
         Ok(buf)
     }
 
@@ -1012,11 +1007,7 @@ pub(super) mod _os {
                 std::mem::transmute::<[i32; 2], i64>(distance_to_move)
             }
         };
-        if res < 0 {
-            Err(errno_err(vm))
-        } else {
-            Ok(res)
-        }
+        if res < 0 { Err(errno_err(vm)) } else { Ok(res) }
     }
 
     #[pyfunction]
@@ -1101,7 +1092,7 @@ pub(super) mod _os {
             (Some(_), Some(_)) => {
                 return Err(vm.new_value_error(
                     "utime: you may specify either 'times' or 'ns' but not both".to_owned(),
-                ))
+                ));
             }
         };
         utime_impl(args.path, acc, modif, args.dir_fd, args.follow_symlinks, vm)
@@ -1139,11 +1130,7 @@ pub(super) mod _os {
                         },
                     )
                 };
-                if ret < 0 {
-                    Err(errno_err(vm))
-                } else {
-                    Ok(())
-                }
+                if ret < 0 { Err(errno_err(vm)) } else { Ok(()) }
             }
             #[cfg(target_os = "redox")]
             {
diff --git a/vm/src/stdlib/posix.rs b/vm/src/stdlib/posix.rs
index 1b843bab60..05b1d8addd 100644
--- a/vm/src/stdlib/posix.rs
+++ b/vm/src/stdlib/posix.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 use std::os::unix::io::RawFd;
 
 pub fn raw_set_inheritable(fd: RawFd, inheritable: bool) -> nix::Result<()> {
@@ -21,16 +21,16 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 #[pymodule(name = "posix", with(super::os::_os))]
 pub mod module {
     use crate::{
+        AsObject, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
         builtins::{PyDictRef, PyInt, PyListRef, PyStrRef, PyTupleRef, PyTypeRef},
         convert::{IntoPyException, ToPyObject, TryFromObject},
         function::{Either, KwArgs, OptionalArg},
         ospath::{IOErrorBuilder, OsPath, OsPathOrFd},
         stdlib::os::{
-            errno_err, DirFd, FollowSymlinks, SupportFunc, TargetIsDirectory, _os, fs_metadata,
+            _os, DirFd, FollowSymlinks, SupportFunc, TargetIsDirectory, errno_err, fs_metadata,
         },
         types::{Constructor, Representable},
         utils::ToCString,
-        AsObject, Py, PyObjectRef, PyPayload, PyResult, VirtualMachine,
     };
     use bitflags::bitflags;
     use nix::{
@@ -352,11 +352,7 @@ pub mod module {
         {
             let [] = args.dir_fd.0;
             let res = unsafe { libc::symlink(src.as_ptr(), dst.as_ptr()) };
-            if res < 0 {
-                Err(errno_err(vm))
-            } else {
-                Ok(())
-            }
+            if res < 0 { Err(errno_err(vm)) } else { Ok(()) }
         }
     }
 
@@ -604,21 +600,13 @@ pub mod module {
                     )
                 },
             };
-            if ret != 0 {
-                Err(errno_err(vm))
-            } else {
-                Ok(())
-            }
+            if ret != 0 { Err(errno_err(vm)) } else { Ok(()) }
         }
         #[cfg(target_vendor = "apple")]
         fn mknod(self, vm: &VirtualMachine) -> PyResult<()> {
             let [] = self.dir_fd.0;
             let ret = self._mknod(vm)?;
-            if ret != 0 {
-                Err(errno_err(vm))
-            } else {
-                Ok(())
-            }
+            if ret != 0 { Err(errno_err(vm)) } else { Ok(()) }
         }
     }
 
@@ -863,7 +851,7 @@ pub mod module {
     #[pyfunction]
     fn set_blocking(fd: RawFd, blocking: bool, vm: &VirtualMachine) -> PyResult<()> {
         let _set_flag = || {
-            use nix::fcntl::{fcntl, FcntlArg, OFlag};
+            use nix::fcntl::{FcntlArg, OFlag, fcntl};
 
             let flags = OFlag::from_bits_truncate(fcntl(fd, FcntlArg::F_GETFL)?);
             let mut new_flags = flags;
@@ -971,7 +959,7 @@ pub mod module {
     #[cfg(any(target_os = "macos", target_os = "freebsd", target_os = "netbsd",))]
     #[pyfunction]
     fn lchmod(path: OsPath, mode: u32, vm: &VirtualMachine) -> PyResult<()> {
-        extern "C" {
+        unsafe extern "C" {
             fn lchmod(path: *const libc::c_char, mode: libc::mode_t) -> libc::c_int;
         }
         let c_path = path.clone().into_cstring(vm)?;
@@ -1605,7 +1593,7 @@ pub mod module {
     // from libstd:
     // https://github.com/rust-lang/rust/blob/daecab3a784f28082df90cebb204998051f3557d/src/libstd/sys/unix/fs.rs#L1251
     #[cfg(target_os = "macos")]
-    extern "C" {
+    unsafe extern "C" {
         fn fcopyfile(
             in_fd: libc::c_int,
             out_fd: libc::c_int,
@@ -1618,11 +1606,7 @@ pub mod module {
     #[pyfunction]
     fn _fcopyfile(in_fd: i32, out_fd: i32, flags: i32, vm: &VirtualMachine) -> PyResult<()> {
         let ret = unsafe { fcopyfile(in_fd, out_fd, std::ptr::null_mut(), flags as u32) };
-        if ret < 0 {
-            Err(errno_err(vm))
-        } else {
-            Ok(())
-        }
+        if ret < 0 { Err(errno_err(vm)) } else { Ok(()) }
     }
 
     #[pyfunction]
@@ -2299,7 +2283,7 @@ pub mod module {
 
     #[cfg(target_os = "linux")]
     unsafe fn sys_getrandom(buf: *mut libc::c_void, buflen: usize, flags: u32) -> isize {
-        libc::syscall(libc::SYS_getrandom, buf, buflen, flags as usize) as _
+        unsafe { libc::syscall(libc::SYS_getrandom, buf, buflen, flags as usize) as _ }
     }
 
     #[cfg(target_os = "linux")]
diff --git a/vm/src/stdlib/posix_compat.rs b/vm/src/stdlib/posix_compat.rs
index 95ed932fe5..334aa597ce 100644
--- a/vm/src/stdlib/posix_compat.rs
+++ b/vm/src/stdlib/posix_compat.rs
@@ -1,5 +1,5 @@
 //! `posix` compatible module for `not(any(unix, windows))`
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = module::make_module(vm);
@@ -10,10 +10,10 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 #[pymodule(name = "posix", with(super::os::_os))]
 pub(crate) mod module {
     use crate::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::PyStrRef,
         ospath::OsPath,
-        stdlib::os::{DirFd, SupportFunc, TargetIsDirectory, _os},
-        PyObjectRef, PyResult, VirtualMachine,
+        stdlib::os::{_os, DirFd, SupportFunc, TargetIsDirectory},
     };
     use std::env;
 
diff --git a/vm/src/stdlib/pwd.rs b/vm/src/stdlib/pwd.rs
index 0edca9c0a6..f6c277242c 100644
--- a/vm/src/stdlib/pwd.rs
+++ b/vm/src/stdlib/pwd.rs
@@ -3,11 +3,11 @@ pub(crate) use pwd::make_module;
 #[pymodule]
 mod pwd {
     use crate::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::{PyIntRef, PyStrRef},
         convert::{IntoPyException, ToPyObject},
         exceptions,
         types::PyStructSequence,
-        PyObjectRef, PyResult, VirtualMachine,
     };
     use nix::unistd::{self, User};
     use std::ptr::NonNull;
diff --git a/vm/src/stdlib/signal.rs b/vm/src/stdlib/signal.rs
index 8c5db53d17..0c47ca082e 100644
--- a/vm/src/stdlib/signal.rs
+++ b/vm/src/stdlib/signal.rs
@@ -1,4 +1,4 @@
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = _signal::make_module(vm);
@@ -13,10 +13,10 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 pub(crate) mod _signal {
     #[cfg(any(unix, windows))]
     use crate::{
-        convert::{IntoPyException, TryFromBorrowedObject},
         Py,
+        convert::{IntoPyException, TryFromBorrowedObject},
     };
-    use crate::{signal, PyObjectRef, PyResult, VirtualMachine};
+    use crate::{PyObjectRef, PyResult, VirtualMachine, signal};
     use std::sync::atomic::{self, Ordering};
 
     #[cfg(any(unix, windows))]
@@ -78,7 +78,7 @@ pub(crate) mod _signal {
     pub const SIG_ERR: sighandler_t = -1 as _;
 
     #[cfg(all(unix, not(target_os = "redox")))]
-    extern "C" {
+    unsafe extern "C" {
         fn siginterrupt(sig: i32, flag: i32) -> i32;
     }
 
diff --git a/vm/src/stdlib/sre.rs b/vm/src/stdlib/sre.rs
index 8442002fa5..7d620c13d9 100644
--- a/vm/src/stdlib/sre.rs
+++ b/vm/src/stdlib/sre.rs
@@ -3,7 +3,8 @@ pub(crate) use _sre::make_module;
 #[pymodule]
 mod _sre {
     use crate::{
-        atomic_func,
+        Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject,
+        TryFromObject, VirtualMachine, atomic_func,
         builtins::{
             PyCallableIterator, PyDictRef, PyGenericAlias, PyInt, PyList, PyListRef, PyStr,
             PyStrRef, PyTuple, PyTupleRef, PyTypeRef,
@@ -14,16 +15,14 @@ mod _sre {
         protocol::{PyBuffer, PyCallable, PyMappingMethods},
         stdlib::sys,
         types::{AsMapping, Comparable, Hashable, Representable},
-        Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, TryFromBorrowedObject,
-        TryFromObject, VirtualMachine,
     };
     use core::str;
     use crossbeam_utils::atomic::AtomicCell;
     use itertools::Itertools;
     use num_traits::ToPrimitive;
     use rustpython_sre_engine::{
-        string::{lower_ascii, lower_unicode, upper_unicode},
         Request, SearchIter, SreFlag, State, StrDrive,
+        string::{lower_ascii, lower_unicode, upper_unicode},
     };
 
     #[pyattr]
diff --git a/vm/src/stdlib/string.rs b/vm/src/stdlib/string.rs
index cedff92d96..8a8a182732 100644
--- a/vm/src/stdlib/string.rs
+++ b/vm/src/stdlib/string.rs
@@ -7,10 +7,10 @@ pub(crate) use _string::make_module;
 mod _string {
     use crate::common::ascii;
     use crate::{
+        PyObjectRef, PyResult, VirtualMachine,
         builtins::{PyList, PyStrRef},
         convert::ToPyException,
         convert::ToPyObject,
-        PyObjectRef, PyResult, VirtualMachine,
     };
     use rustpython_format::{
         FieldName, FieldNamePart, FieldType, FormatPart, FormatString, FromTemplate,
diff --git a/vm/src/stdlib/symtable.rs b/vm/src/stdlib/symtable.rs
index 10d79e9a8b..13a4105111 100644
--- a/vm/src/stdlib/symtable.rs
+++ b/vm/src/stdlib/symtable.rs
@@ -3,7 +3,7 @@ pub(crate) use symtable::make_module;
 #[pymodule]
 mod symtable {
     use crate::{
-        builtins::PyStrRef, compiler, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
+        PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine, builtins::PyStrRef, compiler,
     };
     use rustpython_codegen::symboltable::{
         Symbol, SymbolFlags, SymbolScope, SymbolTable, SymbolTableType,
diff --git a/vm/src/stdlib/sys.rs b/vm/src/stdlib/sys.rs
index 59414b5fdd..dfaab20f2a 100644
--- a/vm/src/stdlib/sys.rs
+++ b/vm/src/stdlib/sys.rs
@@ -1,10 +1,11 @@
-use crate::{builtins::PyModule, convert::ToPyObject, Py, PyResult, VirtualMachine};
+use crate::{Py, PyResult, VirtualMachine, builtins::PyModule, convert::ToPyObject};
 
-pub(crate) use sys::{UnraisableHookArgs, __module_def, DOC, MAXSIZE, MULTIARCH};
+pub(crate) use sys::{__module_def, DOC, MAXSIZE, MULTIARCH, UnraisableHookArgs};
 
 #[pymodule]
 mod sys {
     use crate::{
+        AsObject, PyObject, PyObjectRef, PyRef, PyRefExact, PyResult,
         builtins::{
             PyBaseExceptionRef, PyDictRef, PyNamespace, PyStr, PyStrRef, PyTupleRef, PyTypeRef,
         },
@@ -19,7 +20,6 @@ mod sys {
         types::PyStructSequence,
         version,
         vm::{Settings, VirtualMachine},
-        AsObject, PyObject, PyObjectRef, PyRef, PyRefExact, PyResult,
     };
     use num_traits::ToPrimitive;
     use std::{
@@ -85,11 +85,7 @@ mod sys {
     #[pyattr]
     fn default_prefix(_vm: &VirtualMachine) -> &'static str {
         // TODO: the windows one doesn't really make sense
-        if cfg!(windows) {
-            "C:"
-        } else {
-            "/usr/local"
-        }
+        if cfg!(windows) { "C:" } else { "/usr/local" }
     }
     #[pyattr]
     fn prefix(vm: &VirtualMachine) -> &'static str {
@@ -574,9 +570,11 @@ mod sys {
         if vm.is_none(unraisable.exc_type.as_object()) {
             // TODO: early return, but with what error?
         }
-        assert!(unraisable
-            .exc_type
-            .fast_issubclass(vm.ctx.exceptions.base_exception_type));
+        assert!(
+            unraisable
+                .exc_type
+                .fast_issubclass(vm.ctx.exceptions.base_exception_type)
+        );
 
         // TODO: print module name and qualname
 
diff --git a/vm/src/stdlib/sysconfigdata.rs b/vm/src/stdlib/sysconfigdata.rs
index 929227ac11..90e46b83b9 100644
--- a/vm/src/stdlib/sysconfigdata.rs
+++ b/vm/src/stdlib/sysconfigdata.rs
@@ -2,7 +2,7 @@ pub(crate) use _sysconfigdata::make_module;
 
 #[pymodule]
 pub(crate) mod _sysconfigdata {
-    use crate::{builtins::PyDictRef, convert::ToPyObject, stdlib::sys::MULTIARCH, VirtualMachine};
+    use crate::{VirtualMachine, builtins::PyDictRef, convert::ToPyObject, stdlib::sys::MULTIARCH};
 
     #[pyattr]
     fn build_time_vars(vm: &VirtualMachine) -> PyDictRef {
diff --git a/vm/src/stdlib/thread.rs b/vm/src/stdlib/thread.rs
index 63e66474d1..bca7930437 100644
--- a/vm/src/stdlib/thread.rs
+++ b/vm/src/stdlib/thread.rs
@@ -1,20 +1,20 @@
 //! Implementation of the _thread module
 #[cfg_attr(target_arch = "wasm32", allow(unused_imports))]
-pub(crate) use _thread::{make_module, RawRMutex};
+pub(crate) use _thread::{RawRMutex, make_module};
 
 #[pymodule]
 pub(crate) mod _thread {
     use crate::{
+        AsObject, Py, PyPayload, PyRef, PyResult, VirtualMachine,
         builtins::{PyDictRef, PyStr, PyTupleRef, PyTypeRef},
         convert::ToPyException,
         function::{ArgCallable, Either, FuncArgs, KwArgs, OptionalArg, PySetterValue},
         types::{Constructor, GetAttr, Representable, SetAttr},
-        AsObject, Py, PyPayload, PyRef, PyResult, VirtualMachine,
     };
     use crossbeam_utils::atomic::AtomicCell;
     use parking_lot::{
-        lock_api::{RawMutex as RawMutexT, RawMutexTimed, RawReentrantMutex},
         RawMutex, RawThreadId,
+        lock_api::{RawMutex as RawMutexT, RawMutexTimed, RawReentrantMutex},
     };
     use std::{cell::RefCell, fmt, thread, time::Duration};
     use thread_local::ThreadLocal;
diff --git a/vm/src/stdlib/time.rs b/vm/src/stdlib/time.rs
index 566650d0f2..37a518e504 100644
--- a/vm/src/stdlib/time.rs
+++ b/vm/src/stdlib/time.rs
@@ -2,7 +2,7 @@
 
 // See also:
 // https://docs.python.org/3/library/time.html
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub use decl::time;
 
@@ -17,7 +17,7 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 
 #[cfg(not(target_env = "msvc"))]
 #[cfg(not(target_arch = "wasm32"))]
-extern "C" {
+unsafe extern "C" {
     #[cfg(not(target_os = "freebsd"))]
     #[link_name = "daylight"]
     static c_daylight: std::ffi::c_int;
@@ -33,16 +33,19 @@ extern "C" {
 #[pymodule(name = "time", with(platform))]
 mod decl {
     use crate::{
+        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyStrRef, PyTypeRef},
         function::{Either, FuncArgs, OptionalArg},
         types::PyStructSequence,
-        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     };
     use chrono::{
-        naive::{NaiveDate, NaiveDateTime, NaiveTime},
         DateTime, Datelike, Timelike,
+        naive::{NaiveDate, NaiveDateTime, NaiveTime},
     };
     use std::time::Duration;
+    #[cfg(target_env = "msvc")]
+    #[cfg(not(target_arch = "wasm32"))]
+    use windows::Win32::System::Time;
 
     #[allow(dead_code)]
     pub(super) const SEC_TO_MS: i64 = 1000;
@@ -152,6 +155,15 @@ mod decl {
         Ok(get_perf_time(vm)?.as_nanos())
     }
 
+    #[cfg(target_env = "msvc")]
+    #[cfg(not(target_arch = "wasm32"))]
+    fn get_tz_info() -> Time::TIME_ZONE_INFORMATION {
+        let mut info = Time::TIME_ZONE_INFORMATION::default();
+        let info_ptr = &mut info as *mut Time::TIME_ZONE_INFORMATION;
+        let _ = unsafe { Time::GetTimeZoneInformation(info_ptr) };
+        info
+    }
+
     // #[pyfunction]
     // fn tzset() {
     //     unsafe { super::_tzset() };
@@ -164,6 +176,15 @@ mod decl {
         unsafe { super::c_timezone }
     }
 
+    #[cfg(target_env = "msvc")]
+    #[cfg(not(target_arch = "wasm32"))]
+    #[pyattr]
+    fn timezone(_vm: &VirtualMachine) -> i32 {
+        let info = get_tz_info();
+        // https://users.rust-lang.org/t/accessing-tzname-and-similar-constants-in-windows/125771/3
+        (info.Bias + info.StandardBias) * 60
+    }
+
     #[cfg(not(target_os = "freebsd"))]
     #[cfg(not(target_env = "msvc"))]
     #[cfg(not(target_arch = "wasm32"))]
@@ -172,6 +193,15 @@ mod decl {
         unsafe { super::c_daylight }
     }
 
+    #[cfg(target_env = "msvc")]
+    #[cfg(not(target_arch = "wasm32"))]
+    #[pyattr]
+    fn daylight(_vm: &VirtualMachine) -> i32 {
+        let info = get_tz_info();
+        // https://users.rust-lang.org/t/accessing-tzname-and-similar-constants-in-windows/125771/3
+        (info.StandardBias != info.DaylightBias) as i32
+    }
+
     #[cfg(not(target_env = "msvc"))]
     #[cfg(not(target_arch = "wasm32"))]
     #[pyattr]
@@ -179,11 +209,29 @@ mod decl {
         use crate::builtins::tuple::IntoPyTuple;
 
         unsafe fn to_str(s: *const std::ffi::c_char) -> String {
-            std::ffi::CStr::from_ptr(s).to_string_lossy().into_owned()
+            unsafe { std::ffi::CStr::from_ptr(s) }
+                .to_string_lossy()
+                .into_owned()
         }
         unsafe { (to_str(super::c_tzname[0]), to_str(super::c_tzname[1])) }.into_pytuple(vm)
     }
 
+    #[cfg(target_env = "msvc")]
+    #[cfg(not(target_arch = "wasm32"))]
+    #[pyattr]
+    fn tzname(vm: &VirtualMachine) -> crate::builtins::PyTupleRef {
+        use crate::builtins::tuple::IntoPyTuple;
+        let info = get_tz_info();
+        let standard = widestring::decode_utf16_lossy(info.StandardName)
+            .filter(|&c| c != '\0')
+            .collect::<String>();
+        let daylight = widestring::decode_utf16_lossy(info.DaylightName)
+            .filter(|&c| c != '\0')
+            .collect::<String>();
+        let tz_name = (&*standard, &*daylight);
+        tz_name.into_pytuple(vm)
+    }
+
     fn pyobj_to_date_time(
         value: Either<f64, i64>,
         vm: &VirtualMachine,
@@ -461,9 +509,9 @@ mod platform {
     use super::decl::{SEC_TO_NS, US_TO_NS};
     #[cfg_attr(target_os = "macos", allow(unused_imports))]
     use crate::{
+        PyObject, PyRef, PyResult, TryFromBorrowedObject, VirtualMachine,
         builtins::{PyNamespace, PyStrRef},
         convert::IntoPyException,
-        PyObject, PyRef, PyResult, TryFromBorrowedObject, VirtualMachine,
     };
     use nix::{sys::time::TimeSpec, time::ClockId};
     use std::time::Duration;
@@ -673,7 +721,7 @@ mod platform {
         target_os = "openbsd",
     ))]
     pub(super) fn get_process_time(vm: &VirtualMachine) -> PyResult<Duration> {
-        use nix::sys::resource::{getrusage, UsageWho};
+        use nix::sys::resource::{UsageWho, getrusage};
         fn from_timeval(tv: libc::timeval, vm: &VirtualMachine) -> PyResult<i64> {
             (|tv: libc::timeval| {
                 let t = tv.tv_sec.checked_mul(SEC_TO_NS)?;
@@ -695,11 +743,11 @@ mod platform {
 #[cfg(windows)]
 #[pymodule]
 mod platform {
-    use super::decl::{time_muldiv, MS_TO_NS, SEC_TO_NS};
+    use super::decl::{MS_TO_NS, SEC_TO_NS, time_muldiv};
     use crate::{
+        PyRef, PyResult, VirtualMachine,
         builtins::{PyNamespace, PyStrRef},
         stdlib::os::errno_err,
-        PyRef, PyResult, VirtualMachine,
     };
     use std::time::Duration;
     use windows_sys::Win32::{
diff --git a/vm/src/stdlib/typing.rs b/vm/src/stdlib/typing.rs
index daa0180325..c266e811ca 100644
--- a/vm/src/stdlib/typing.rs
+++ b/vm/src/stdlib/typing.rs
@@ -3,9 +3,9 @@ pub(crate) use _typing::make_module;
 #[pymodule]
 pub(crate) mod _typing {
     use crate::{
-        builtins::{pystr::AsPyStr, PyGenericAlias, PyTupleRef, PyTypeRef},
-        function::IntoFuncArgs,
         PyObjectRef, PyPayload, PyResult, VirtualMachine,
+        builtins::{PyGenericAlias, PyTupleRef, PyTypeRef, pystr::AsPyStr},
+        function::IntoFuncArgs,
     };
 
     pub(crate) fn _call_typing_func_object<'a>(
@@ -75,18 +75,31 @@ pub(crate) mod _typing {
     #[pyclass(name = "ParamSpec")]
     #[derive(Debug, PyPayload)]
     #[allow(dead_code)]
-    struct ParamSpec {}
+    pub(crate) struct ParamSpec {
+        name: PyObjectRef,
+    }
+
     #[pyclass(flags(BASETYPE))]
     impl ParamSpec {}
 
+    pub(crate) fn make_paramspec(name: PyObjectRef) -> ParamSpec {
+        ParamSpec { name }
+    }
+
     #[pyattr]
     #[pyclass(name = "TypeVarTuple")]
     #[derive(Debug, PyPayload)]
     #[allow(dead_code)]
-    pub(crate) struct TypeVarTuple {}
+    pub(crate) struct TypeVarTuple {
+        name: PyObjectRef,
+    }
     #[pyclass(flags(BASETYPE))]
     impl TypeVarTuple {}
 
+    pub(crate) fn make_typevartuple(name: PyObjectRef) -> TypeVarTuple {
+        TypeVarTuple { name }
+    }
+
     #[pyattr]
     #[pyclass(name = "ParamSpecArgs")]
     #[derive(Debug, PyPayload)]
diff --git a/vm/src/stdlib/warnings.rs b/vm/src/stdlib/warnings.rs
index be5ad8131e..a8ffee4579 100644
--- a/vm/src/stdlib/warnings.rs
+++ b/vm/src/stdlib/warnings.rs
@@ -1,6 +1,6 @@
 pub(crate) use _warnings::make_module;
 
-use crate::{builtins::PyType, Py, PyResult, VirtualMachine};
+use crate::{Py, PyResult, VirtualMachine, builtins::PyType};
 
 pub fn warn(
     category: &Py<PyType>,
@@ -20,9 +20,9 @@ pub fn warn(
 #[pymodule]
 mod _warnings {
     use crate::{
+        PyResult, VirtualMachine,
         builtins::{PyStrRef, PyTypeRef},
         function::OptionalArg,
-        PyResult, VirtualMachine,
     };
 
     #[derive(FromArgs)]
diff --git a/vm/src/stdlib/weakref.rs b/vm/src/stdlib/weakref.rs
index 3ef0de6155..7d8924ff52 100644
--- a/vm/src/stdlib/weakref.rs
+++ b/vm/src/stdlib/weakref.rs
@@ -9,8 +9,8 @@ pub(crate) use _weakref::make_module;
 #[pymodule]
 mod _weakref {
     use crate::{
-        builtins::{PyDictRef, PyTypeRef, PyWeak},
         PyObjectRef, PyResult, VirtualMachine,
+        builtins::{PyDictRef, PyTypeRef, PyWeak},
     };
 
     #[pyattr(name = "ref")]
diff --git a/vm/src/stdlib/winapi.rs b/vm/src/stdlib/winapi.rs
index ad6db12474..c1edb2739e 100644
--- a/vm/src/stdlib/winapi.rs
+++ b/vm/src/stdlib/winapi.rs
@@ -4,18 +4,18 @@ pub(crate) use _winapi::make_module;
 #[pymodule]
 mod _winapi {
     use crate::{
+        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
         builtins::PyStrRef,
         common::windows::ToWideString,
         convert::{ToPyException, ToPyResult},
         function::{ArgMapping, ArgSequence, OptionalArg},
         stdlib::os::errno_err,
         windows::WindowsSysResult,
-        PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     };
     use std::ptr::{null, null_mut};
     use windows::{
-        core::PCWSTR,
         Win32::Foundation::{HANDLE, HINSTANCE, MAX_PATH},
+        core::PCWSTR,
     };
     use windows_sys::Win32::Foundation::{BOOL, HANDLE as RAW_HANDLE};
 
@@ -28,10 +28,20 @@ mod _winapi {
             ERROR_PIPE_CONNECTED, ERROR_SEM_TIMEOUT, GENERIC_READ, GENERIC_WRITE, STILL_ACTIVE,
             WAIT_ABANDONED, WAIT_ABANDONED_0, WAIT_OBJECT_0, WAIT_TIMEOUT,
         },
+        Globalization::{
+            LCMAP_FULLWIDTH, LCMAP_HALFWIDTH, LCMAP_HIRAGANA, LCMAP_KATAKANA,
+            LCMAP_LINGUISTIC_CASING, LCMAP_LOWERCASE, LCMAP_SIMPLIFIED_CHINESE, LCMAP_TITLECASE,
+            LCMAP_TRADITIONAL_CHINESE, LCMAP_UPPERCASE,
+        },
         Storage::FileSystem::{
-            FILE_FLAG_FIRST_PIPE_INSTANCE, FILE_FLAG_OVERLAPPED, FILE_GENERIC_READ,
-            FILE_GENERIC_WRITE, FILE_TYPE_CHAR, FILE_TYPE_DISK, FILE_TYPE_PIPE, FILE_TYPE_REMOTE,
-            FILE_TYPE_UNKNOWN, OPEN_EXISTING, PIPE_ACCESS_DUPLEX, PIPE_ACCESS_INBOUND, SYNCHRONIZE,
+            COPYFILE2_CALLBACK_CHUNK_FINISHED, COPYFILE2_CALLBACK_CHUNK_STARTED,
+            COPYFILE2_CALLBACK_ERROR, COPYFILE2_CALLBACK_POLL_CONTINUE,
+            COPYFILE2_CALLBACK_STREAM_FINISHED, COPYFILE2_CALLBACK_STREAM_STARTED,
+            COPYFILE2_PROGRESS_CANCEL, COPYFILE2_PROGRESS_CONTINUE, COPYFILE2_PROGRESS_PAUSE,
+            COPYFILE2_PROGRESS_QUIET, COPYFILE2_PROGRESS_STOP, FILE_FLAG_FIRST_PIPE_INSTANCE,
+            FILE_FLAG_OVERLAPPED, FILE_GENERIC_READ, FILE_GENERIC_WRITE, FILE_TYPE_CHAR,
+            FILE_TYPE_DISK, FILE_TYPE_PIPE, FILE_TYPE_REMOTE, FILE_TYPE_UNKNOWN, OPEN_EXISTING,
+            PIPE_ACCESS_DUPLEX, PIPE_ACCESS_INBOUND, SYNCHRONIZE,
         },
         System::{
             Console::{STD_ERROR_HANDLE, STD_INPUT_HANDLE, STD_OUTPUT_HANDLE},
@@ -53,6 +63,13 @@ mod _winapi {
                 IDLE_PRIORITY_CLASS, INFINITE, NORMAL_PRIORITY_CLASS, PROCESS_DUP_HANDLE,
                 REALTIME_PRIORITY_CLASS, STARTF_USESHOWWINDOW, STARTF_USESTDHANDLES,
             },
+            WindowsProgramming::{
+                COPY_FILE_ALLOW_DECRYPTED_DESTINATION, COPY_FILE_COPY_SYMLINK,
+                COPY_FILE_FAIL_IF_EXISTS, COPY_FILE_NO_BUFFERING, COPY_FILE_NO_OFFLOAD,
+                COPY_FILE_OPEN_SOURCE_FOR_WRITE, COPY_FILE_REQUEST_COMPRESSED_TRAFFIC,
+                COPY_FILE_REQUEST_SECURITY_PRIVILEGES, COPY_FILE_RESTARTABLE,
+                COPY_FILE_RESUME_FROM_PAUSE,
+            },
         },
         UI::WindowsAndMessaging::SW_HIDE,
     };
@@ -119,6 +136,11 @@ mod _winapi {
         Ok(HANDLE(target))
     }
 
+    #[pyfunction]
+    fn GetACP() -> u32 {
+        unsafe { windows_sys::Win32::Globalization::GetACP() }
+    }
+
     #[pyfunction]
     fn GetCurrentProcess() -> HANDLE {
         unsafe { windows::Win32::System::Threading::GetCurrentProcess() }
@@ -137,6 +159,16 @@ mod _winapi {
         }
     }
 
+    #[pyfunction]
+    fn GetLastError() -> u32 {
+        unsafe { windows_sys::Win32::Foundation::GetLastError() }
+    }
+
+    #[pyfunction]
+    fn GetVersion() -> u32 {
+        unsafe { windows_sys::Win32::System::SystemInformation::GetVersion() }
+    }
+
     #[derive(FromArgs)]
     struct CreateProcessArgs {
         #[pyarg(positional)]
@@ -249,6 +281,21 @@ mod _winapi {
         ))
     }
 
+    #[pyfunction]
+    fn OpenProcess(
+        desired_access: u32,
+        inherit_handle: bool,
+        process_id: u32,
+    ) -> windows_sys::Win32::Foundation::HANDLE {
+        unsafe {
+            windows_sys::Win32::System::Threading::OpenProcess(
+                desired_access,
+                BOOL::from(inherit_handle),
+                process_id,
+            )
+        }
+    }
+
     #[pyfunction]
     fn NeedCurrentDirectoryForExePath(exe_name: PyStrRef) -> bool {
         let exe_name = exe_name.as_str().to_wide_with_nul();
@@ -447,4 +494,24 @@ mod _winapi {
         let (path, _) = path.split_at(length as usize);
         Ok(String::from_utf16(path).unwrap())
     }
+
+    #[pyfunction]
+    fn OpenMutexW(desired_access: u32, inherit_handle: bool, name: u16) -> PyResult<isize> {
+        let handle = unsafe {
+            windows_sys::Win32::System::Threading::OpenMutexW(
+                desired_access,
+                BOOL::from(inherit_handle),
+                windows_sys::core::PCWSTR::from(name as _),
+            )
+        };
+        // if handle.is_invalid() {
+        //     return Err(errno_err(vm));
+        // }
+        Ok(handle)
+    }
+
+    #[pyfunction]
+    fn ReleaseMutex(handle: isize) -> WindowsSysResult<BOOL> {
+        WindowsSysResult(unsafe { windows_sys::Win32::System::Threading::ReleaseMutex(handle) })
+    }
 }
diff --git a/vm/src/stdlib/winreg.rs b/vm/src/stdlib/winreg.rs
index b368c43a3e..b0dbbfceec 100644
--- a/vm/src/stdlib/winreg.rs
+++ b/vm/src/stdlib/winreg.rs
@@ -1,6 +1,6 @@
 #![allow(non_snake_case)]
 
-use crate::{builtins::PyModule, PyRef, VirtualMachine};
+use crate::{PyRef, VirtualMachine, builtins::PyModule};
 
 pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
     let module = winreg::make_module(vm);
@@ -29,10 +29,10 @@ pub(crate) fn make_module(vm: &VirtualMachine) -> PyRef<PyModule> {
 mod winreg {
     use crate::common::lock::{PyRwLock, PyRwLockReadGuard, PyRwLockWriteGuard};
     use crate::{
-        builtins::PyStrRef, convert::ToPyException, PyObjectRef, PyPayload, PyRef, PyResult,
-        TryFromObject, VirtualMachine,
+        PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine, builtins::PyStrRef,
+        convert::ToPyException,
     };
-    use ::winreg::{enums::RegType, RegKey, RegValue};
+    use ::winreg::{RegKey, RegValue, enums::RegType};
     use std::mem::ManuallyDrop;
     use std::{ffi::OsStr, io};
     use windows_sys::Win32::Foundation;
@@ -47,9 +47,13 @@ mod winreg {
     // value types
     #[pyattr]
     pub use windows_sys::Win32::System::Registry::{
-        REG_BINARY, REG_DWORD, REG_DWORD_BIG_ENDIAN, REG_DWORD_LITTLE_ENDIAN, REG_EXPAND_SZ,
-        REG_FULL_RESOURCE_DESCRIPTOR, REG_LINK, REG_MULTI_SZ, REG_NONE, REG_QWORD,
-        REG_QWORD_LITTLE_ENDIAN, REG_RESOURCE_LIST, REG_RESOURCE_REQUIREMENTS_LIST, REG_SZ,
+        REG_BINARY, REG_CREATED_NEW_KEY, REG_DWORD, REG_DWORD_BIG_ENDIAN, REG_DWORD_LITTLE_ENDIAN,
+        REG_EXPAND_SZ, REG_FULL_RESOURCE_DESCRIPTOR, REG_LINK, REG_MULTI_SZ, REG_NONE,
+        REG_NOTIFY_CHANGE_ATTRIBUTES, REG_NOTIFY_CHANGE_LAST_SET, REG_NOTIFY_CHANGE_NAME,
+        REG_NOTIFY_CHANGE_SECURITY, REG_OPENED_EXISTING_KEY, REG_OPTION_BACKUP_RESTORE,
+        REG_OPTION_CREATE_LINK, REG_OPTION_NON_VOLATILE, REG_OPTION_OPEN_LINK, REG_OPTION_RESERVED,
+        REG_OPTION_VOLATILE, REG_QWORD, REG_QWORD_LITTLE_ENDIAN, REG_RESOURCE_LIST,
+        REG_RESOURCE_REQUIREMENTS_LIST, REG_SZ, REG_WHOLE_HIVE_VOLATILE,
     };
 
     #[pyattr]
@@ -98,7 +102,7 @@ mod winreg {
 
         #[pymethod(magic)]
         fn bool(&self) -> bool {
-            self.key().raw_handle() != 0
+            !self.key().raw_handle().is_null()
         }
         #[pymethod(magic)]
         fn enter(zelf: PyRef<Self>) -> PyRef<Self> {
diff --git a/vm/src/suggestion.rs b/vm/src/suggestion.rs
index d46630a651..2bc9992d43 100644
--- a/vm/src/suggestion.rs
+++ b/vm/src/suggestion.rs
@@ -1,10 +1,10 @@
 use crate::{
+    AsObject, Py, PyObjectRef, VirtualMachine,
     builtins::{PyStr, PyStrRef},
     exceptions::types::PyBaseExceptionRef,
     sliceable::SliceableSequenceOp,
-    AsObject, Py, PyObjectRef, VirtualMachine,
 };
-use rustpython_common::str::levenshtein::{levenshtein_distance, MOVE_COST};
+use rustpython_common::str::levenshtein::{MOVE_COST, levenshtein_distance};
 use std::iter::ExactSizeIterator;
 
 const MAX_CANDIDATE_ITEMS: usize = 750;
@@ -52,10 +52,8 @@ pub fn offer_suggestions(exc: &PyBaseExceptionRef, vm: &VirtualMachine) -> Optio
         calculate_suggestions(vm.dir(Some(obj)).ok()?.borrow_vec().iter(), &name)
     } else if exc.class().is(vm.ctx.exceptions.name_error) {
         let name = exc.as_object().get_attr("name", vm).unwrap();
-        let mut tb = exc.traceback()?;
-        for traceback in tb.iter() {
-            tb = traceback;
-        }
+        let tb = exc.traceback()?;
+        let tb = tb.iter().last().unwrap_or(tb);
 
         let varnames = tb.frame.code.clone().co_varnames(vm);
         if let Some(suggestions) = calculate_suggestions(varnames.iter(), &name) {
diff --git a/vm/src/types/slot.rs b/vm/src/types/slot.rs
index 75f113977d..de651580d9 100644
--- a/vm/src/types/slot.rs
+++ b/vm/src/types/slot.rs
@@ -1,5 +1,6 @@
 use crate::{
-    builtins::{type_::PointerSlot, PyInt, PyStr, PyStrInterned, PyStrRef, PyType, PyTypeRef},
+    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
+    builtins::{PyInt, PyStr, PyStrInterned, PyStrRef, PyType, PyTypeRef, type_::PointerSlot},
     bytecode::ComparisonOperator,
     common::hash::PyHash,
     convert::{ToPyObject, ToPyResult},
@@ -12,7 +13,6 @@ use crate::{
         PyNumberSlots, PySequence, PySequenceMethods,
     },
     vm::Context,
-    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 use crossbeam_utils::atomic::AtomicCell;
 use malachite_bigint::BigInt;
diff --git a/vm/src/types/structseq.rs b/vm/src/types/structseq.rs
index 516e2085af..a0b445ce7d 100644
--- a/vm/src/types/structseq.rs
+++ b/vm/src/types/structseq.rs
@@ -1,8 +1,8 @@
 use crate::{
+    AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     builtins::{PyTuple, PyTupleRef, PyType},
     class::{PyClassImpl, StaticType},
     vm::Context,
-    AsObject, Py, PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
 };
 
 #[pyclass]
diff --git a/vm/src/types/zoo.rs b/vm/src/types/zoo.rs
index 492b584e29..0d39648514 100644
--- a/vm/src/types/zoo.rs
+++ b/vm/src/types/zoo.rs
@@ -1,4 +1,5 @@
 use crate::{
+    Py,
     builtins::{
         asyncgenerator, bool_, builtin_func, bytearray, bytes, classmethod, code, complex,
         coroutine, descriptor, dict, enumerate, filter, float, frame, function, generator,
@@ -10,7 +11,6 @@ use crate::{
     },
     class::StaticType,
     vm::Context,
-    Py,
 };
 
 /// Holder of references to builtin types.
diff --git a/vm/src/utils.rs b/vm/src/utils.rs
index 2c5ff79d3f..e2bc993686 100644
--- a/vm/src/utils.rs
+++ b/vm/src/utils.rs
@@ -1,7 +1,8 @@
 use crate::{
+    PyObjectRef, PyResult, VirtualMachine,
     builtins::PyStr,
     convert::{ToPyException, ToPyObject},
-    PyObjectRef, PyResult, VirtualMachine,
+    exceptions::cstring_error,
 };
 
 pub fn hash_iter<'a, I: IntoIterator<Item = &'a PyObjectRef>>(
@@ -17,22 +18,22 @@ impl ToPyObject for std::convert::Infallible {
     }
 }
 
-pub trait ToCString {
-    fn to_cstring(&self, vm: &VirtualMachine) -> PyResult<std::ffi::CString>;
-}
-
-impl ToCString for &str {
-    fn to_cstring(&self, vm: &VirtualMachine) -> PyResult<std::ffi::CString> {
-        std::ffi::CString::new(*self).map_err(|err| err.to_pyexception(vm))
-    }
-}
-
-impl ToCString for PyStr {
+pub trait ToCString: AsRef<str> {
     fn to_cstring(&self, vm: &VirtualMachine) -> PyResult<std::ffi::CString> {
         std::ffi::CString::new(self.as_ref()).map_err(|err| err.to_pyexception(vm))
     }
+    fn ensure_no_nul(&self, vm: &VirtualMachine) -> PyResult<()> {
+        if self.as_ref().as_bytes().contains(&b'\0') {
+            Err(cstring_error(vm))
+        } else {
+            Ok(())
+        }
+    }
 }
 
+impl ToCString for &str {}
+impl ToCString for PyStr {}
+
 pub(crate) fn collection_repr<'a, I>(
     class_name: Option<&str>,
     prefix: &str,
diff --git a/vm/src/version.rs b/vm/src/version.rs
index 9a75f71142..8c42866a64 100644
--- a/vm/src/version.rs
+++ b/vm/src/version.rs
@@ -1,12 +1,12 @@
 /* Several function to retrieve version information.
  */
 
-use chrono::{prelude::DateTime, Local};
+use chrono::{Local, prelude::DateTime};
 use std::time::{Duration, UNIX_EPOCH};
 
-// = 3.12.0alpha
+// = 3.13.0alpha
 pub const MAJOR: usize = 3;
-pub const MINOR: usize = 12;
+pub const MINOR: usize = 13;
 pub const MICRO: usize = 0;
 pub const RELEASELEVEL: &str = "alpha";
 pub const RELEASELEVEL_N: usize = 0xA;
diff --git a/vm/src/vm/compile.rs b/vm/src/vm/compile.rs
index b7c888ab10..a14e986dac 100644
--- a/vm/src/vm/compile.rs
+++ b/vm/src/vm/compile.rs
@@ -1,9 +1,9 @@
 use crate::{
+    AsObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
     builtins::{PyCode, PyDictRef},
     compiler::{self, CompileError, CompileOpts},
     convert::TryFromObject,
     scope::Scope,
-    AsObject, PyObjectRef, PyRef, PyResult, VirtualMachine,
 };
 
 impl VirtualMachine {
diff --git a/vm/src/vm/context.rs b/vm/src/vm/context.rs
index f67035d0f3..54605704a5 100644
--- a/vm/src/vm/context.rs
+++ b/vm/src/vm/context.rs
@@ -1,6 +1,9 @@
 use crate::{
+    PyResult, VirtualMachine,
     builtins::{
-        bytes,
+        PyBaseException, PyBytes, PyComplex, PyDict, PyDictRef, PyEllipsis, PyFloat, PyFrozenSet,
+        PyInt, PyIntRef, PyList, PyListRef, PyNone, PyNotImplemented, PyStr, PyStrInterned,
+        PyTuple, PyTupleRef, PyType, PyTypeRef, bytes,
         code::{self, PyCode},
         descriptor::{
             MemberGetter, MemberKind, MemberSetter, MemberSetterFunc, PyDescriptorOwned,
@@ -9,9 +12,6 @@ use crate::{
         getset::PyGetSet,
         object, pystr,
         type_::PyAttributes,
-        PyBaseException, PyBytes, PyComplex, PyDict, PyDictRef, PyEllipsis, PyFloat, PyFrozenSet,
-        PyInt, PyIntRef, PyList, PyListRef, PyNone, PyNotImplemented, PyStr, PyStrInterned,
-        PyTuple, PyTupleRef, PyType, PyTypeRef,
     },
     class::{PyClassImpl, StaticType},
     common::rc::PyRc,
@@ -23,7 +23,6 @@ use crate::{
     intern::{InternableString, MaybeInternedString, StringPool},
     object::{Py, PyObjectPayload, PyObjectRef, PyPayload, PyRef},
     types::{PyTypeFlags, PyTypeSlots, TypeZoo},
-    PyResult, VirtualMachine,
 };
 use malachite_bigint::BigInt;
 use num_complex::Complex64;
@@ -62,7 +61,7 @@ macro_rules! declare_const_name {
         impl ConstName {
             unsafe fn new(pool: &StringPool, typ: &PyTypeRef) -> Self {
                 Self {
-                    $($name: pool.intern(stringify!($name), typ.clone()),)*
+                    $($name: unsafe { pool.intern(stringify!($name), typ.clone()) },)*
                 }
             }
         }
diff --git a/vm/src/vm/interpreter.rs b/vm/src/vm/interpreter.rs
index af28ad87ab..a375dbedc1 100644
--- a/vm/src/vm/interpreter.rs
+++ b/vm/src/vm/interpreter.rs
@@ -1,5 +1,5 @@
-use super::{setting::Settings, thread, Context, VirtualMachine};
-use crate::{stdlib::atexit, vm::PyBaseExceptionRef, PyResult};
+use super::{Context, VirtualMachine, setting::Settings, thread};
+use crate::{PyResult, stdlib::atexit, vm::PyBaseExceptionRef};
 use std::sync::atomic::Ordering;
 
 /// The general interface for the VM
@@ -140,8 +140,8 @@ impl Interpreter {
 mod tests {
     use super::*;
     use crate::{
-        builtins::{int, PyStr},
         PyObjectRef,
+        builtins::{PyStr, int},
     };
     use malachite_bigint::ToBigInt;
 
diff --git a/vm/src/vm/mod.rs b/vm/src/vm/mod.rs
index 3d3351055f..05ac245a0a 100644
--- a/vm/src/vm/mod.rs
+++ b/vm/src/vm/mod.rs
@@ -15,12 +15,13 @@ mod vm_object;
 mod vm_ops;
 
 use crate::{
+    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
     builtins::{
+        PyBaseExceptionRef, PyDictRef, PyInt, PyList, PyModule, PyStr, PyStrInterned, PyStrRef,
+        PyTypeRef,
         code::PyCode,
         pystr::AsPyStr,
         tuple::{PyTuple, PyTupleTyped},
-        PyBaseExceptionRef, PyDictRef, PyInt, PyList, PyModule, PyStr, PyStrInterned, PyStrRef,
-        PyTypeRef,
     },
     codecs::CodecsRegistry,
     common::{hash::HashSecret, lock::PyMutex, rc::PyRc},
@@ -33,12 +34,11 @@ use crate::{
     scope::Scope,
     signal, stdlib,
     warn::WarningsState,
-    AsObject, Py, PyObject, PyObjectRef, PyPayload, PyRef, PyResult,
 };
 use crossbeam_utils::atomic::AtomicCell;
 #[cfg(unix)]
 use nix::{
-    sys::signal::{kill, sigaction, SaFlags, SigAction, SigSet, Signal::SIGINT},
+    sys::signal::{SaFlags, SigAction, SigSet, Signal::SIGINT, kill, sigaction},
     unistd::getpid,
 };
 use std::sync::atomic::AtomicBool;
@@ -356,7 +356,9 @@ impl VirtualMachine {
 
         if self.state.settings.allow_external_library && cfg!(feature = "rustpython-compiler") {
             if let Err(e) = import::init_importlib_package(self, importlib) {
-                eprintln!("importlib initialization failed. This is critical for many complicated packages.");
+                eprintln!(
+                    "importlib initialization failed. This is critical for many complicated packages."
+                );
                 self.print_exception(e);
             }
         }
diff --git a/vm/src/vm/vm_new.rs b/vm/src/vm/vm_new.rs
index 55f06e90da..bd42396299 100644
--- a/vm/src/vm/vm_new.rs
+++ b/vm/src/vm/vm_new.rs
@@ -1,15 +1,15 @@
 use crate::{
+    AsObject, Py, PyObject, PyObjectRef, PyRef,
     builtins::{
+        PyBaseException, PyBaseExceptionRef, PyDictRef, PyModule, PyStrRef, PyType, PyTypeRef,
         builtin_func::PyNativeFunction,
         descriptor::PyMethodDescriptor,
         tuple::{IntoPyTuple, PyTupleRef},
-        PyBaseException, PyBaseExceptionRef, PyDictRef, PyModule, PyStrRef, PyType, PyTypeRef,
     },
     convert::ToPyObject,
     function::{IntoPyNativeFn, PyMethodFlags},
     scope::Scope,
     vm::VirtualMachine,
-    AsObject, Py, PyObject, PyObjectRef, PyRef,
 };
 
 /// Collection of object creation helpers
@@ -365,7 +365,15 @@ impl VirtualMachine {
         let actual_class = obj.class();
         let actual_type = &*actual_class.name();
         let expected_type = &*class.name();
-        let msg = format!("Expected {msg} '{expected_type}' but '{actual_type}' found");
+        let msg = format!("Expected {msg} '{expected_type}' but '{actual_type}' found.");
+        #[cfg(debug_assertions)]
+        let msg = if class.get_id() == actual_class.get_id() {
+            let mut msg = msg;
+            msg += " Did you forget to add `#[pyclass(with(Constructor))]`?";
+            msg
+        } else {
+            msg
+        };
         self.new_exception_msg(error_type.to_owned(), msg)
     }
 
diff --git a/vm/src/vm/vm_object.rs b/vm/src/vm/vm_object.rs
index b687eea34c..103078272d 100644
--- a/vm/src/vm/vm_object.rs
+++ b/vm/src/vm/vm_object.rs
@@ -1,6 +1,6 @@
 use super::PyMethod;
 use crate::{
-    builtins::{pystr::AsPyStr, PyBaseExceptionRef, PyList, PyStrInterned},
+    builtins::{PyBaseExceptionRef, PyList, PyStrInterned, pystr::AsPyStr},
     function::IntoFuncArgs,
     identifier,
     object::{AsObject, PyObject, PyObjectRef, PyResult},
@@ -85,11 +85,7 @@ impl VirtualMachine {
         obj.is(&self.ctx.none)
     }
     pub fn option_if_none(&self, obj: PyObjectRef) -> Option<PyObjectRef> {
-        if self.is_none(&obj) {
-            None
-        } else {
-            Some(obj)
-        }
+        if self.is_none(&obj) { None } else { Some(obj) }
     }
     pub fn unwrap_or_none(&self, obj: Option<PyObjectRef>) -> PyObjectRef {
         obj.unwrap_or_else(|| self.ctx.none())
diff --git a/vm/src/vm/vm_ops.rs b/vm/src/vm/vm_ops.rs
index 56c32d2927..09f849a1a1 100644
--- a/vm/src/vm/vm_ops.rs
+++ b/vm/src/vm/vm_ops.rs
@@ -114,7 +114,7 @@ impl VirtualMachine {
                     Ok(None)
                 } else {
                     Err(e)
-                }
+                };
             }
         };
         let hint = result
@@ -298,8 +298,8 @@ impl VirtualMachine {
         }
 
         if let Some(slot_c) = class_c.slots.as_number.left_ternary_op(op_slot) {
-            if slot_a.is_some_and(|slot_a| slot_a != slot_c)
-                && slot_b.is_some_and(|slot_b| slot_b != slot_c)
+            if slot_a.is_some_and(|slot_a| !std::ptr::fn_addr_eq(slot_a, slot_c))
+                && slot_b.is_some_and(|slot_b| !std::ptr::fn_addr_eq(slot_b, slot_c))
             {
                 let ret = slot_c(a, b, c, self)?;
                 if !ret.is(&self.ctx.not_implemented) {
diff --git a/vm/src/warn.rs b/vm/src/warn.rs
index ab316c8559..b2055225a0 100644
--- a/vm/src/warn.rs
+++ b/vm/src/warn.rs
@@ -1,11 +1,11 @@
 use crate::{
+    AsObject, Context, Py, PyObjectRef, PyResult, VirtualMachine,
     builtins::{
         PyDict, PyDictRef, PyListRef, PyStr, PyStrInterned, PyStrRef, PyTuple, PyTupleRef,
         PyTypeRef,
     },
     convert::{IntoObject, TryFromObject},
     types::PyComparisonOp,
-    AsObject, Context, Py, PyObjectRef, PyResult, VirtualMachine,
 };
 
 pub struct WarningsState {
@@ -17,15 +17,16 @@ pub struct WarningsState {
 
 impl WarningsState {
     fn create_filter(ctx: &Context) -> PyListRef {
-        ctx.new_list(vec![ctx
-            .new_tuple(vec![
+        ctx.new_list(vec![
+            ctx.new_tuple(vec![
                 ctx.new_str("__main__").into(),
                 ctx.types.none_type.as_object().to_owned(),
                 ctx.exceptions.warning.as_object().to_owned(),
                 ctx.new_str("ACTION").into(),
                 ctx.new_int(0).into(),
             ])
-            .into()])
+            .into(),
+        ])
     }
 
     pub fn init_state(ctx: &Context) -> WarningsState {
diff --git a/vm/src/windows.rs b/vm/src/windows.rs
index f98bb1de63..f4f4dad0b3 100644
--- a/vm/src/windows.rs
+++ b/vm/src/windows.rs
@@ -1,11 +1,11 @@
 use crate::common::fileutils::{
-    windows::{get_file_information_by_name, FILE_INFO_BY_NAME_CLASS},
     StatStruct,
+    windows::{FILE_INFO_BY_NAME_CLASS, get_file_information_by_name},
 };
 use crate::{
+    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     convert::{ToPyObject, ToPyResult},
     stdlib::os::errno_err,
-    PyObjectRef, PyResult, TryFromObject, VirtualMachine,
 };
 use std::{ffi::OsStr, time::SystemTime};
 use windows::Win32::Foundation::HANDLE;
@@ -139,7 +139,7 @@ fn file_id(path: &OsStr) -> std::io::Result<u64> {
     use windows_sys::Win32::{
         Foundation::HANDLE,
         Storage::FileSystem::{
-            GetFileInformationByHandle, BY_HANDLE_FILE_INFORMATION, FILE_FLAG_BACKUP_SEMANTICS,
+            BY_HANDLE_FILE_INFORMATION, FILE_FLAG_BACKUP_SEMANTICS, GetFileInformationByHandle,
         },
     };
 
diff --git a/vm/sre_engine/Cargo.toml b/vm/sre_engine/Cargo.toml
index 28f98a3212..504652f3a7 100644
--- a/vm/sre_engine/Cargo.toml
+++ b/vm/sre_engine/Cargo.toml
@@ -10,7 +10,17 @@ rust-version.workspace = true
 repository.workspace = true
 license.workspace = true
 
+[[bench]]
+name = "benches"
+harness = false
+
 [dependencies]
 num_enum = { workspace = true }
 bitflags = { workspace = true }
 optional = "0.5"
+
+[dev-dependencies]
+criterion = { workspace = true }
+
+[lints]
+workspace = true
diff --git a/vm/sre_engine/LICENSE b/vm/sre_engine/LICENSE
index 7213274e0f..e2aa2ed952 100644
--- a/vm/sre_engine/LICENSE
+++ b/vm/sre_engine/LICENSE
@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020 RustPython Team
+Copyright (c) 2025 RustPython Team
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/vm/sre_engine/benches/benches.rs b/vm/sre_engine/benches/benches.rs
index e31c73b0d0..ee49b036de 100644
--- a/vm/sre_engine/benches/benches.rs
+++ b/vm/sre_engine/benches/benches.rs
@@ -1,11 +1,9 @@
-#![feature(test)]
-
-extern crate test;
-use test::Bencher;
-
 use rustpython_sre_engine::{Request, State, StrDrive};
 
+use criterion::{BenchmarkId, Criterion, criterion_group, criterion_main};
+
 struct Pattern {
+    pattern: &'static str,
     code: &'static [u32],
 }
 
@@ -25,52 +23,51 @@ impl Pattern {
     }
 }
 
-#[bench]
-fn benchmarks(b: &mut Bencher) {
+fn basic(c: &mut Criterion) {
     // # test common prefix
     // pattern p1 = re.compile('Python|Perl') # , 'Perl'),    # Alternation
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p1 = Pattern { code: &[14, 8, 1, 4, 6, 1, 1, 80, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 1] };
+    #[rustfmt::skip] let p1 = Pattern { pattern: "Python|Perl", code: &[14, 8, 1, 4, 6, 1, 1, 80, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 1] };
     // END GENERATED
     // pattern p2 = re.compile('(Python|Perl)') #, 'Perl'),  # Grouped alternation
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p2 = Pattern { code: &[14, 8, 1, 4, 6, 1, 0, 80, 0, 17, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 17, 1, 1] };
+    #[rustfmt::skip] let p2 = Pattern { pattern: "(Python|Perl)", code: &[14, 8, 1, 4, 6, 1, 0, 80, 0, 17, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 17, 1, 1] };
     // END GENERATED
     // pattern p3 = re.compile('Python|Perl|Tcl') #, 'Perl'),        # Alternation
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p3 = Pattern { code: &[14, 9, 4, 3, 6, 16, 80, 16, 84, 0, 7, 15, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 22, 11, 16, 80, 16, 101, 16, 114, 16, 108, 15, 11, 9, 16, 84, 16, 99, 16, 108, 15, 2, 0, 1] };
+    #[rustfmt::skip] let p3 = Pattern { pattern: "Python|Perl|Tcl", code: &[14, 9, 4, 3, 6, 16, 80, 16, 84, 0, 7, 15, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 22, 11, 16, 80, 16, 101, 16, 114, 16, 108, 15, 11, 9, 16, 84, 16, 99, 16, 108, 15, 2, 0, 1] };
     // END GENERATED
     // pattern p4 = re.compile('(Python|Perl|Tcl)') #, 'Perl'),      # Grouped alternation
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p4 = Pattern { code: &[14, 9, 4, 3, 6, 16, 80, 16, 84, 0, 17, 0, 7, 15, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 22, 11, 16, 80, 16, 101, 16, 114, 16, 108, 15, 11, 9, 16, 84, 16, 99, 16, 108, 15, 2, 0, 17, 1, 1] };
+    #[rustfmt::skip] let p4 = Pattern { pattern: "(Python|Perl|Tcl)", code: &[14, 9, 4, 3, 6, 16, 80, 16, 84, 0, 17, 0, 7, 15, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 22, 11, 16, 80, 16, 101, 16, 114, 16, 108, 15, 11, 9, 16, 84, 16, 99, 16, 108, 15, 2, 0, 17, 1, 1] };
     // END GENERATED
     // pattern p5 = re.compile('(Python)\\1') #, 'PythonPython'),    # Backreference
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p5 = Pattern { code: &[14, 18, 1, 12, 12, 6, 0, 80, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 17, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 11, 0, 1] };
+    #[rustfmt::skip] let p5 = Pattern { pattern: "(Python)\\1", code: &[14, 18, 1, 12, 12, 6, 0, 80, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 17, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 11, 0, 1] };
     // END GENERATED
     // pattern p6 = re.compile('([0a-z][a-z0-9]*,)+') #, 'a5,b7,c9,'), # Disable the fastmap optimization
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p6 = Pattern { code: &[14, 4, 0, 2, 4294967295, 23, 31, 1, 4294967295, 17, 0, 13, 7, 16, 48, 22, 97, 122, 0, 24, 13, 0, 4294967295, 13, 8, 22, 97, 122, 22, 48, 57, 0, 1, 16, 44, 17, 1, 18, 1] };
+    #[rustfmt::skip] let p6 = Pattern { pattern: "([0a-z][a-z0-9]*,)+", code: &[14, 4, 0, 2, 4294967295, 23, 31, 1, 4294967295, 17, 0, 13, 7, 16, 48, 22, 97, 122, 0, 24, 13, 0, 4294967295, 13, 8, 22, 97, 122, 22, 48, 57, 0, 1, 16, 44, 17, 1, 18, 1] };
     // END GENERATED
     // pattern p7 = re.compile('([a-z][a-z0-9]*,)+') #, 'a5,b7,c9,'), # A few sets
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p7 = Pattern { code: &[14, 4, 0, 2, 4294967295, 23, 29, 1, 4294967295, 17, 0, 13, 5, 22, 97, 122, 0, 24, 13, 0, 4294967295, 13, 8, 22, 97, 122, 22, 48, 57, 0, 1, 16, 44, 17, 1, 18, 1] };
+    #[rustfmt::skip] let p7 = Pattern { pattern: "([a-z][a-z0-9]*,)+", code: &[14, 4, 0, 2, 4294967295, 23, 29, 1, 4294967295, 17, 0, 13, 5, 22, 97, 122, 0, 24, 13, 0, 4294967295, 13, 8, 22, 97, 122, 22, 48, 57, 0, 1, 16, 44, 17, 1, 18, 1] };
     // END GENERATED
     // pattern p8 = re.compile('Python') #, 'Python'),               # Simple text literal
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p8 = Pattern { code: &[14, 18, 3, 6, 6, 6, 6, 80, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 1] };
+    #[rustfmt::skip] let p8 = Pattern { pattern: "Python", code: &[14, 18, 3, 6, 6, 6, 6, 80, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 1] };
     // END GENERATED
     // pattern p9 = re.compile('.*Python') #, 'Python'),             # Bad text literal
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p9 = Pattern { code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 1] };
+    #[rustfmt::skip] let p9 = Pattern { pattern: ".*Python", code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 1] };
     // END GENERATED
     // pattern p10 = re.compile('.*Python.*') #, 'Python'),           # Worse text literal
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p10 = Pattern { code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 24, 5, 0, 4294967295, 2, 1, 1] };
+    #[rustfmt::skip] let p10 = Pattern { pattern: ".*Python.*", code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 24, 5, 0, 4294967295, 2, 1, 1] };
     // END GENERATED
     // pattern p11 = re.compile('.*(Python)') #, 'Python'),           # Bad text literal with grouping
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p11 = Pattern { code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 17, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 1] };
+    #[rustfmt::skip] let p11 = Pattern { pattern: ".*(Python)", code: &[14, 4, 0, 6, 4294967295, 24, 5, 0, 4294967295, 2, 1, 17, 0, 16, 80, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 1] };
     // END GENERATED
 
     let tests = [
@@ -87,25 +84,33 @@ fn benchmarks(b: &mut Bencher) {
         (p11, "Python"),
     ];
 
-    b.iter(move || {
-        for (p, s) in &tests {
-            let (req, mut state) = p.state(s.clone());
-            assert!(state.search(req));
-            let (req, mut state) = p.state(s.clone());
-            assert!(state.pymatch(&req));
-            let (mut req, mut state) = p.state(s.clone());
-            req.match_all = true;
-            assert!(state.pymatch(&req));
-            let s2 = format!("{}{}{}", " ".repeat(10000), s, " ".repeat(10000));
-            let (req, mut state) = p.state_range(s2.as_str(), 0..usize::MAX);
-            assert!(state.search(req));
-            let (req, mut state) = p.state_range(s2.as_str(), 10000..usize::MAX);
-            assert!(state.pymatch(&req));
-            let (req, mut state) = p.state_range(s2.as_str(), 10000..10000 + s.len());
-            assert!(state.pymatch(&req));
-            let (mut req, mut state) = p.state_range(s2.as_str(), 10000..10000 + s.len());
-            req.match_all = true;
-            assert!(state.pymatch(&req));
-        }
-    })
+    let mut group = c.benchmark_group("basic");
+
+    for (p, s) in tests {
+        group.bench_with_input(BenchmarkId::new(p.pattern, s), s, |b, s| {
+            b.iter(|| {
+                let (req, mut state) = p.state(s);
+                assert!(state.search(req));
+                let (req, mut state) = p.state(s);
+                assert!(state.pymatch(&req));
+                let (mut req, mut state) = p.state(s);
+                req.match_all = true;
+                assert!(state.pymatch(&req));
+                let s2 = format!("{}{}{}", " ".repeat(10000), s, " ".repeat(10000));
+                let (req, mut state) = p.state_range(s2.as_str(), 0..usize::MAX);
+                assert!(state.search(req));
+                let (req, mut state) = p.state_range(s2.as_str(), 10000..usize::MAX);
+                assert!(state.pymatch(&req));
+                let (req, mut state) = p.state_range(s2.as_str(), 10000..10000 + s.len());
+                assert!(state.pymatch(&req));
+                let (mut req, mut state) = p.state_range(s2.as_str(), 10000..10000 + s.len());
+                req.match_all = true;
+                assert!(state.pymatch(&req));
+            });
+        });
+    }
 }
+
+criterion_group!(benches, basic);
+
+criterion_main!(benches);
diff --git a/vm/sre_engine/generate_tests.py b/vm/sre_engine/generate_tests.py
index 8adf043f29..6621c56813 100644
--- a/vm/sre_engine/generate_tests.py
+++ b/vm/sre_engine/generate_tests.py
@@ -1,9 +1,6 @@
 import os
 from pathlib import Path
 import re
-import sre_constants
-import sre_compile
-import sre_parse
 import json
 from itertools import chain
 
@@ -11,13 +8,13 @@
 sre_engine_magic = int(m.group(1))
 del m
 
-assert sre_constants.MAGIC == sre_engine_magic
+assert re._constants.MAGIC == sre_engine_magic
 
 class CompiledPattern:
     @classmethod
     def compile(cls, pattern, flags=0):
-        p = sre_parse.parse(pattern)
-        code = sre_compile._code(p, flags)
+        p = re._parser.parse(pattern)
+        code = re._compiler._code(p, flags)
         self = cls()
         self.pattern = pattern
         self.code = code
@@ -28,12 +25,32 @@ def compile(cls, pattern, flags=0):
     setattr(CompiledPattern, k, v)
 
 
+class EscapeRustStr:
+    hardcoded = {
+        ord('\r'): '\\r',
+        ord('\t'): '\\t',
+        ord('\r'): '\\r',
+        ord('\n'): '\\n',
+        ord('\\'): '\\\\',
+        ord('\''): '\\\'',
+        ord('\"'): '\\\"',
+    }
+    @classmethod
+    def __class_getitem__(cls, ch):
+        if (rpl := cls.hardcoded.get(ch)) is not None:
+            return rpl
+        if ch in range(0x20, 0x7f):
+            return ch
+        return f"\\u{{{ch:x}}}"
+def rust_str(s):
+    return '"' + s.translate(EscapeRustStr) + '"'
+
 # matches `// pattern {varname} = re.compile(...)`
 pattern_pattern = re.compile(r"^((\s*)\/\/\s*pattern\s+(\w+)\s+=\s+(.+?))$(?:.+?END GENERATED)?", re.M | re.S)
 def replace_compiled(m):
     line, indent, varname, pattern = m.groups()
     pattern = eval(pattern, {"re": CompiledPattern})
-    pattern = f"Pattern {{ code: &{json.dumps(pattern.code)} }}"
+    pattern = f"Pattern {{ pattern: {rust_str(pattern.pattern)}, code: &{json.dumps(pattern.code)} }}"
     return f'''{line}
 {indent}// START GENERATED by generate_tests.py
 {indent}#[rustfmt::skip] let {varname} = {pattern};
diff --git a/vm/sre_engine/src/engine.rs b/vm/sre_engine/src/engine.rs
index 77f4ccdf36..3425da3371 100644
--- a/vm/sre_engine/src/engine.rs
+++ b/vm/sre_engine/src/engine.rs
@@ -5,7 +5,7 @@ use crate::string::{
     is_uni_word, is_word, lower_ascii, lower_locate, lower_unicode, upper_locate, upper_unicode,
 };
 
-use super::{SreAtCode, SreCatCode, SreInfo, SreOpcode, StrDrive, StringCursor, MAXREPEAT};
+use super::{MAXREPEAT, SreAtCode, SreCatCode, SreInfo, SreOpcode, StrDrive, StringCursor};
 use optional::Optioned;
 use std::{convert::TryFrom, ptr::null};
 
diff --git a/vm/sre_engine/src/lib.rs b/vm/sre_engine/src/lib.rs
index fd9f367dc6..08c21de9df 100644
--- a/vm/sre_engine/src/lib.rs
+++ b/vm/sre_engine/src/lib.rs
@@ -2,7 +2,7 @@ pub mod constants;
 pub mod engine;
 pub mod string;
 
-pub use constants::{SreAtCode, SreCatCode, SreFlag, SreInfo, SreOpcode, SRE_MAGIC};
+pub use constants::{SRE_MAGIC, SreAtCode, SreCatCode, SreFlag, SreInfo, SreOpcode};
 pub use engine::{Request, SearchIter, State};
 pub use string::{StrDrive, StringCursor};
 
diff --git a/vm/sre_engine/src/string.rs b/vm/sre_engine/src/string.rs
index ca8b3179dc..77e0f3e772 100644
--- a/vm/sre_engine/src/string.rs
+++ b/vm/sre_engine/src/string.rs
@@ -157,8 +157,8 @@ impl StrDrive for &str {
 #[inline]
 unsafe fn next_code_point(ptr: &mut *const u8) -> u32 {
     // Decode UTF-8
-    let x = **ptr;
-    *ptr = ptr.offset(1);
+    let x = unsafe { **ptr };
+    *ptr = unsafe { ptr.offset(1) };
 
     if x < 128 {
         return x as u32;
@@ -170,26 +170,26 @@ unsafe fn next_code_point(ptr: &mut *const u8) -> u32 {
     let init = utf8_first_byte(x, 2);
     // SAFETY: `bytes` produces an UTF-8-like string,
     // so the iterator must produce a value here.
-    let y = **ptr;
-    *ptr = ptr.offset(1);
+    let y = unsafe { **ptr };
+    *ptr = unsafe { ptr.offset(1) };
     let mut ch = utf8_acc_cont_byte(init, y);
     if x >= 0xE0 {
         // [[x y z] w] case
         // 5th bit in 0xE0 .. 0xEF is always clear, so `init` is still valid
         // SAFETY: `bytes` produces an UTF-8-like string,
         // so the iterator must produce a value here.
-        let z = **ptr;
-        *ptr = ptr.offset(1);
+        let z = unsafe { **ptr };
+        *ptr = unsafe { ptr.offset(1) };
         let y_z = utf8_acc_cont_byte((y & CONT_MASK) as u32, z);
-        ch = init << 12 | y_z;
+        ch = (init << 12) | y_z;
         if x >= 0xF0 {
             // [x y z w] case
             // use only the lower 3 bits of `init`
             // SAFETY: `bytes` produces an UTF-8-like string,
             // so the iterator must produce a value here.
-            let w = **ptr;
-            *ptr = ptr.offset(1);
-            ch = (init & 7) << 18 | utf8_acc_cont_byte(y_z, w);
+            let w = unsafe { **ptr };
+            *ptr = unsafe { ptr.offset(1) };
+            ch = ((init & 7) << 18) | utf8_acc_cont_byte(y_z, w);
         }
     }
 
@@ -205,8 +205,8 @@ unsafe fn next_code_point(ptr: &mut *const u8) -> u32 {
 #[inline]
 unsafe fn next_code_point_reverse(ptr: &mut *const u8) -> u32 {
     // Decode UTF-8
-    *ptr = ptr.offset(-1);
-    let w = match **ptr {
+    *ptr = unsafe { ptr.offset(-1) };
+    let w = match unsafe { **ptr } {
         next_byte if next_byte < 128 => return next_byte as u32,
         back_byte => back_byte,
     };
@@ -216,20 +216,20 @@ unsafe fn next_code_point_reverse(ptr: &mut *const u8) -> u32 {
     let mut ch;
     // SAFETY: `bytes` produces an UTF-8-like string,
     // so the iterator must produce a value here.
-    *ptr = ptr.offset(-1);
-    let z = **ptr;
+    *ptr = unsafe { ptr.offset(-1) };
+    let z = unsafe { **ptr };
     ch = utf8_first_byte(z, 2);
     if utf8_is_cont_byte(z) {
         // SAFETY: `bytes` produces an UTF-8-like string,
         // so the iterator must produce a value here.
-        *ptr = ptr.offset(-1);
-        let y = **ptr;
+        *ptr = unsafe { ptr.offset(-1) };
+        let y = unsafe { **ptr };
         ch = utf8_first_byte(y, 3);
         if utf8_is_cont_byte(y) {
             // SAFETY: `bytes` produces an UTF-8-like string,
             // so the iterator must produce a value here.
-            *ptr = ptr.offset(-1);
-            let x = **ptr;
+            *ptr = unsafe { ptr.offset(-1) };
+            let x = unsafe { **ptr };
             ch = utf8_first_byte(x, 4);
             ch = utf8_acc_cont_byte(ch, y);
         }
diff --git a/vm/sre_engine/tests/tests.rs b/vm/sre_engine/tests/tests.rs
index 53494c5e3d..0946fd64ca 100644
--- a/vm/sre_engine/tests/tests.rs
+++ b/vm/sre_engine/tests/tests.rs
@@ -1,6 +1,7 @@
 use rustpython_sre_engine::{Request, State, StrDrive};
 
 struct Pattern {
+    pattern: &'static str,
     code: &'static [u32],
 }
 
@@ -16,7 +17,7 @@ impl Pattern {
 fn test_2427() {
     // pattern lookbehind = re.compile(r'(?<!\.)x\b')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let lookbehind = Pattern { code: &[14, 4, 0, 1, 1, 5, 5, 1, 16, 46, 1, 16, 120, 6, 10, 1] };
+    #[rustfmt::skip] let lookbehind = Pattern { pattern: "(?<!\\.)x\\b", code: &[14, 4, 0, 1, 1, 5, 5, 1, 16, 46, 1, 16, 120, 6, 10, 1] };
     // END GENERATED
     let (req, mut state) = lookbehind.state("x");
     assert!(state.pymatch(&req));
@@ -26,7 +27,7 @@ fn test_2427() {
 fn test_assert() {
     // pattern positive_lookbehind = re.compile(r'(?<=abc)def')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let positive_lookbehind = Pattern { code: &[14, 4, 0, 3, 3, 4, 9, 3, 16, 97, 16, 98, 16, 99, 1, 16, 100, 16, 101, 16, 102, 1] };
+    #[rustfmt::skip] let positive_lookbehind = Pattern { pattern: "(?<=abc)def", code: &[14, 4, 0, 3, 3, 4, 9, 3, 16, 97, 16, 98, 16, 99, 1, 16, 100, 16, 101, 16, 102, 1] };
     // END GENERATED
     let (req, mut state) = positive_lookbehind.state("abcdef");
     assert!(state.search(req));
@@ -36,7 +37,7 @@ fn test_assert() {
 fn test_string_boundaries() {
     // pattern big_b = re.compile(r'\B')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let big_b = Pattern { code: &[14, 4, 0, 0, 0, 6, 11, 1] };
+    #[rustfmt::skip] let big_b = Pattern { pattern: "\\B", code: &[14, 4, 0, 0, 0, 6, 11, 1] };
     // END GENERATED
     let (req, mut state) = big_b.state("");
     assert!(!state.search(req));
@@ -46,7 +47,7 @@ fn test_string_boundaries() {
 fn test_zerowidth() {
     // pattern p = re.compile(r'\b|:+')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 0, 4294967295, 7, 5, 6, 10, 15, 12, 10, 24, 6, 1, 4294967295, 16, 58, 1, 15, 2, 0, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "\\b|:+", code: &[14, 4, 0, 0, 4294967295, 7, 5, 6, 10, 15, 12, 10, 24, 6, 1, 4294967295, 16, 58, 1, 15, 2, 0, 1] };
     // END GENERATED
     let (mut req, mut state) = p.state("a:");
     req.must_advance = true;
@@ -59,7 +60,7 @@ fn test_repeat_context_panic() {
     use optional::Optioned;
     // pattern p = re.compile(r'(?:a*?(xx)??z)*')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 0, 4294967295, 23, 25, 0, 4294967295, 26, 6, 0, 4294967295, 16, 97, 1, 23, 11, 0, 1, 17, 0, 16, 120, 16, 120, 17, 1, 19, 16, 122, 18, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "(?:a*?(xx)??z)*", code: &[14, 4, 0, 0, 4294967295, 23, 25, 0, 4294967295, 26, 6, 0, 4294967295, 16, 97, 1, 23, 11, 0, 1, 17, 0, 16, 120, 16, 120, 17, 1, 19, 16, 122, 18, 1] };
     // END GENERATED
     let (req, mut state) = p.state("axxzaz");
     assert!(state.pymatch(&req));
@@ -73,7 +74,7 @@ fn test_repeat_context_panic() {
 fn test_double_max_until() {
     // pattern p = re.compile(r'((1)?)*')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 0, 4294967295, 23, 18, 0, 4294967295, 17, 0, 23, 9, 0, 1, 17, 2, 16, 49, 17, 3, 18, 17, 1, 18, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "((1)?)*", code: &[14, 4, 0, 0, 4294967295, 23, 18, 0, 4294967295, 17, 0, 23, 9, 0, 1, 17, 2, 16, 49, 17, 3, 18, 17, 1, 18, 1] };
     // END GENERATED
     let (req, mut state) = p.state("1111");
     assert!(state.pymatch(&req));
@@ -84,7 +85,7 @@ fn test_double_max_until() {
 fn test_info_single() {
     // pattern p = re.compile(r'aa*')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 8, 1, 1, 4294967295, 1, 1, 97, 0, 16, 97, 24, 6, 0, 4294967295, 16, 97, 1, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "aa*", code: &[14, 8, 1, 1, 4294967295, 1, 1, 97, 0, 16, 97, 24, 6, 0, 4294967295, 16, 97, 1, 1] };
     // END GENERATED
     let (req, mut state) = p.state("baaaa");
     assert!(state.search(req));
@@ -96,7 +97,7 @@ fn test_info_single() {
 fn test_info_single2() {
     // pattern p = re.compile(r'Python|Perl')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 8, 1, 4, 6, 1, 1, 80, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "Python|Perl", code: &[14, 8, 1, 4, 6, 1, 1, 80, 0, 16, 80, 7, 13, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 15, 11, 9, 16, 101, 16, 114, 16, 108, 15, 2, 0, 1] };
     // END GENERATED
     let (req, mut state) = p.state("Perl");
     assert!(state.search(req));
@@ -106,7 +107,7 @@ fn test_info_single2() {
 fn test_info_literal() {
     // pattern p = re.compile(r'ababc+')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 14, 1, 5, 4294967295, 4, 4, 97, 98, 97, 98, 0, 0, 1, 2, 16, 97, 16, 98, 16, 97, 16, 98, 24, 6, 1, 4294967295, 16, 99, 1, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "ababc+", code: &[14, 14, 1, 5, 4294967295, 4, 4, 97, 98, 97, 98, 0, 0, 1, 2, 16, 97, 16, 98, 16, 97, 16, 98, 24, 6, 1, 4294967295, 16, 99, 1, 1] };
     // END GENERATED
     let (req, mut state) = p.state("!ababc");
     assert!(state.search(req));
@@ -116,7 +117,7 @@ fn test_info_literal() {
 fn test_info_literal2() {
     // pattern p = re.compile(r'(python)\1')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 18, 1, 12, 12, 6, 0, 112, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 17, 0, 16, 112, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 11, 0, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "(python)\\1", code: &[14, 18, 1, 12, 12, 6, 0, 112, 121, 116, 104, 111, 110, 0, 0, 0, 0, 0, 0, 17, 0, 16, 112, 16, 121, 16, 116, 16, 104, 16, 111, 16, 110, 17, 1, 11, 0, 1] };
     // END GENERATED
     let (req, mut state) = p.state("pythonpython");
     assert!(state.search(req));
@@ -126,7 +127,7 @@ fn test_info_literal2() {
 fn test_repeat_in_assertions() {
     // pattern p = re.compile('^([ab]*?)(?=(b)?)c', re.IGNORECASE)
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 1, 4294967295, 6, 0, 17, 0, 26, 10, 0, 4294967295, 39, 5, 22, 97, 98, 0, 1, 17, 1, 4, 14, 0, 23, 9, 0, 1, 17, 2, 40, 98, 17, 3, 18, 1, 40, 99, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "^([ab]*?)(?=(b)?)c", code: &[14, 4, 0, 1, 4294967295, 6, 0, 17, 0, 26, 10, 0, 4294967295, 39, 5, 22, 97, 98, 0, 1, 17, 1, 4, 14, 0, 23, 9, 0, 1, 17, 2, 40, 98, 17, 3, 18, 1, 40, 99, 1] };
     // END GENERATED
     let (req, mut state) = p.state("abc");
     assert!(state.search(req));
@@ -136,7 +137,7 @@ fn test_repeat_in_assertions() {
 fn test_possessive_quantifier() {
     // pattern p = re.compile('e++a')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 2, 4294967295, 29, 6, 1, 4294967295, 16, 101, 1, 16, 97, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "e++a", code: &[14, 4, 0, 2, 4294967295, 29, 6, 1, 4294967295, 16, 101, 1, 16, 97, 1] };
     // END GENERATED
     let (req, mut state) = p.state("eeea");
     assert!(state.pymatch(&req));
@@ -146,7 +147,7 @@ fn test_possessive_quantifier() {
 fn test_possessive_atomic_group() {
     // pattern p = re.compile('(?>x)++x')
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 2, 4294967295, 28, 8, 1, 4294967295, 27, 4, 16, 120, 1, 1, 16, 120, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "(?>x)++x", code: &[14, 4, 0, 2, 4294967295, 28, 8, 1, 4294967295, 27, 4, 16, 120, 1, 1, 16, 120, 1] };
     // END GENERATED
     let (req, mut state) = p.state("xxx");
     assert!(!state.pymatch(&req));
@@ -156,7 +157,7 @@ fn test_possessive_atomic_group() {
 fn test_bug_20998() {
     // pattern p = re.compile('[a-c]+', re.I)
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 1, 4294967295, 24, 10, 1, 4294967295, 39, 5, 22, 97, 99, 0, 1, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "[a-c]+", code: &[14, 4, 0, 1, 4294967295, 24, 10, 1, 4294967295, 39, 5, 22, 97, 99, 0, 1, 1] };
     // END GENERATED
     let (mut req, mut state) = p.state("ABC");
     req.match_all = true;
@@ -168,7 +169,7 @@ fn test_bug_20998() {
 fn test_bigcharset() {
     // pattern p = re.compile('[a-z]*', re.I)
     // START GENERATED by generate_tests.py
-    #[rustfmt::skip] let p = Pattern { code: &[14, 4, 0, 0, 4294967295, 24, 97, 0, 4294967295, 39, 92, 10, 3, 33685760, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 0, 0, 0, 134217726, 0, 0, 0, 0, 0, 131072, 0, 2147483648, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1] };
+    #[rustfmt::skip] let p = Pattern { pattern: "[a-z]*", code: &[14, 4, 0, 0, 4294967295, 24, 97, 0, 4294967295, 39, 92, 10, 3, 33685760, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 33686018, 0, 0, 0, 134217726, 0, 0, 0, 0, 0, 131072, 0, 2147483648, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1] };
     // END GENERATED
     let (req, mut state) = p.state("x ");
     assert!(state.pymatch(&req));
@@ -178,4 +179,7 @@ fn test_bigcharset() {
 #[test]
 fn test_search_nonascii() {
     // pattern p = re.compile('\xe0+')
+    // START GENERATED by generate_tests.py
+    #[rustfmt::skip] let p = Pattern { pattern: "\u{e0}+", code: &[14, 4, 0, 1, 4294967295, 24, 6, 1, 4294967295, 16, 224, 1, 1] };
+    // END GENERATED
 }
diff --git a/wasm/lib/.cargo/config.toml b/wasm/lib/.cargo/config.toml
new file mode 100644
index 0000000000..ce1e7c694a
--- /dev/null
+++ b/wasm/lib/.cargo/config.toml
@@ -0,0 +1,5 @@
+[build]
+target = "wasm32-unknown-unknown"
+
+[target.wasm32-unknown-unknown]
+rustflags = ["--cfg=getrandom_backend=\"wasm_js\""]
diff --git a/wasm/lib/Cargo.toml b/wasm/lib/Cargo.toml
index 1e5c37f4ef..4703cb9f4a 100644
--- a/wasm/lib/Cargo.toml
+++ b/wasm/lib/Cargo.toml
@@ -28,6 +28,9 @@ rustpython-parser = { workspace = true }
 serde = { workspace = true }
 wasm-bindgen = { workspace = true }
 
+# remove once getrandom 0.2 is no longer otherwise in the dependency tree
+getrandom = { version = "0.2", features = ["js"] }
+
 console_error_panic_hook = "0.1"
 js-sys = "0.3"
 serde-wasm-bindgen = "0.3.1"
@@ -47,4 +50,4 @@ web-sys = { version = "0.3", features = [
 wasm-opt = false#["-O1"]
 
 [lints]
-workspace = true
\ No newline at end of file
+workspace = true
diff --git a/wasm/lib/src/browser_module.rs b/wasm/lib/src/browser_module.rs
index 86a3ea3ab3..f8d1b2ebc3 100644
--- a/wasm/lib/src/browser_module.rs
+++ b/wasm/lib/src/browser_module.rs
@@ -7,14 +7,14 @@ mod _browser {
     use crate::{convert, js_module::PyPromise, vm_class::weak_vm, wasm_builtins::window};
     use js_sys::Promise;
     use rustpython_vm::{
+        PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
         builtins::{PyDictRef, PyStrRef},
         class::PyClassImpl,
         convert::ToPyObject,
         function::{ArgCallable, OptionalArg},
         import::import_source,
-        PyObjectRef, PyPayload, PyRef, PyResult, VirtualMachine,
     };
-    use wasm_bindgen::{prelude::*, JsCast};
+    use wasm_bindgen::{JsCast, prelude::*};
     use wasm_bindgen_futures::JsFuture;
 
     enum FetchResponseFormat {
diff --git a/wasm/lib/src/convert.rs b/wasm/lib/src/convert.rs
index 0bf1d21c95..d4fb068e6c 100644
--- a/wasm/lib/src/convert.rs
+++ b/wasm/lib/src/convert.rs
@@ -1,17 +1,18 @@
 #![allow(clippy::empty_docs)] // TODO: remove it later. false positive by wasm-bindgen generated code
 
 use crate::js_module;
-use crate::vm_class::{stored_vm_from_wasm, WASMVirtualMachine};
+use crate::vm_class::{WASMVirtualMachine, stored_vm_from_wasm};
 use js_sys::{Array, ArrayBuffer, Object, Promise, Reflect, SyntaxError, Uint8Array};
-use rustpython_parser::{lexer::LexicalErrorType, ParseErrorType};
+use rustpython_parser::{ParseErrorType, lexer::LexicalErrorType};
 use rustpython_vm::{
+    AsObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine,
     builtins::PyBaseExceptionRef,
     compiler::{CompileError, CompileErrorType},
     exceptions,
     function::{ArgBytesLike, FuncArgs},
-    py_serde, AsObject, PyObjectRef, PyPayload, PyResult, TryFromBorrowedObject, VirtualMachine,
+    py_serde,
 };
-use wasm_bindgen::{closure::Closure, prelude::*, JsCast};
+use wasm_bindgen::{JsCast, closure::Closure, prelude::*};
 
 #[wasm_bindgen(inline_js = r"
 export class PyError extends Error {
diff --git a/wasm/lib/src/js_module.rs b/wasm/lib/src/js_module.rs
index f0c5378c35..e25499df4d 100644
--- a/wasm/lib/src/js_module.rs
+++ b/wasm/lib/src/js_module.rs
@@ -5,21 +5,21 @@ use rustpython_vm::VirtualMachine;
 mod _js {
     use crate::{
         convert,
-        vm_class::{stored_vm_from_wasm, WASMVirtualMachine},
+        vm_class::{WASMVirtualMachine, stored_vm_from_wasm},
         weak_vm,
     };
     use js_sys::{Array, Object, Promise, Reflect};
     use rustpython_vm::{
+        Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
         builtins::{PyBaseExceptionRef, PyFloat, PyStrRef, PyType, PyTypeRef},
         convert::{IntoObject, ToPyObject},
         function::{ArgCallable, OptionalArg, OptionalOption, PosArgs},
         protocol::PyIterReturn,
         types::{IterNext, Representable, SelfIter},
-        Py, PyObjectRef, PyPayload, PyRef, PyResult, TryFromObject, VirtualMachine,
     };
     use std::{cell, fmt, future};
-    use wasm_bindgen::{closure::Closure, prelude::*, JsCast};
-    use wasm_bindgen_futures::{future_to_promise, JsFuture};
+    use wasm_bindgen::{JsCast, closure::Closure, prelude::*};
+    use wasm_bindgen_futures::{JsFuture, future_to_promise};
 
     #[wasm_bindgen(inline_js = "
     export function has_prop(target, prop) { return prop in Object(target); }
diff --git a/wasm/lib/src/vm_class.rs b/wasm/lib/src/vm_class.rs
index 0c62bb32e7..c04877f7e3 100644
--- a/wasm/lib/src/vm_class.rs
+++ b/wasm/lib/src/vm_class.rs
@@ -5,10 +5,10 @@ use crate::{
 };
 use js_sys::{Object, TypeError};
 use rustpython_vm::{
+    Interpreter, PyObjectRef, PyPayload, PyRef, PyResult, Settings, VirtualMachine,
     builtins::{PyModule, PyWeak},
     compiler::Mode,
     scope::Scope,
-    Interpreter, PyObjectRef, PyPayload, PyRef, PyResult, Settings, VirtualMachine,
 };
 use std::{
     cell::RefCell,
@@ -233,7 +233,7 @@ impl WASMVirtualMachine {
 
     #[wasm_bindgen(js_name = addToScope)]
     pub fn add_to_scope(&self, name: String, value: JsValue) -> Result<(), JsValue> {
-        self.with_vm(move |vm, StoredVirtualMachine { ref scope, .. }| {
+        self.with_vm(move |vm, StoredVirtualMachine { scope, .. }| {
             let value = convert::js_to_py(vm, value);
             scope.globals.set_item(&name, value, vm).into_js(vm)
         })?
@@ -335,7 +335,7 @@ impl WASMVirtualMachine {
         mode: Mode,
         source_path: Option<String>,
     ) -> Result<JsValue, JsValue> {
-        self.with_vm(|vm, StoredVirtualMachine { ref scope, .. }| {
+        self.with_vm(|vm, StoredVirtualMachine { scope, .. }| {
             let source_path = source_path.unwrap_or_else(|| "<wasm>".to_owned());
             let code = vm.compile(source, mode, source_path);
             let code = code.map_err(convert::syntax_err)?;
diff --git a/wasm/lib/src/wasm_builtins.rs b/wasm/lib/src/wasm_builtins.rs
index 59d7880af4..79423fc250 100644
--- a/wasm/lib/src/wasm_builtins.rs
+++ b/wasm/lib/src/wasm_builtins.rs
@@ -4,7 +4,7 @@
 //! desktop.
 //! Implements functions listed here: https://docs.python.org/3/library/builtins.html.
 
-use rustpython_vm::{builtins::PyStrRef, PyObjectRef, PyRef, PyResult, VirtualMachine};
+use rustpython_vm::{PyObjectRef, PyRef, PyResult, VirtualMachine, builtins::PyStrRef};
 use web_sys::{self, console};
 
 pub(crate) fn window() -> web_sys::Window {
diff --git a/wasm/wasm-unknown-test/.cargo/config.toml b/wasm/wasm-unknown-test/.cargo/config.toml
new file mode 100644
index 0000000000..f86ad96761
--- /dev/null
+++ b/wasm/wasm-unknown-test/.cargo/config.toml
@@ -0,0 +1,5 @@
+[build]
+target = "wasm32-unknown-unknown"
+
+[target.wasm32-unknown-unknown]
+rustflags = ["--cfg=getrandom_backend=\"custom\""]
diff --git a/wasm/wasm-unknown-test/Cargo.toml b/wasm/wasm-unknown-test/Cargo.toml
index f5e0b55786..ca8b15cfc5 100644
--- a/wasm/wasm-unknown-test/Cargo.toml
+++ b/wasm/wasm-unknown-test/Cargo.toml
@@ -8,6 +8,7 @@ crate-type = ["cdylib"]
 
 [dependencies]
 getrandom = { version = "0.2.12", features = ["custom"] }
+getrandom_03 = { package = "getrandom", version = "0.3" }
 rustpython-vm = { path = "../../vm", default-features = false, features = ["compiler"] }
 
 [workspace]
diff --git a/wasm/wasm-unknown-test/src/lib.rs b/wasm/wasm-unknown-test/src/lib.rs
index fd043aea3a..cfdc445574 100644
--- a/wasm/wasm-unknown-test/src/lib.rs
+++ b/wasm/wasm-unknown-test/src/lib.rs
@@ -14,3 +14,11 @@ fn getrandom_always_fail(_buf: &mut [u8]) -> Result<(), getrandom::Error> {
 }
 
 getrandom::register_custom_getrandom!(getrandom_always_fail);
+
+#[unsafe(no_mangle)]
+unsafe extern "Rust" fn __getrandom_v03_custom(
+    _dest: *mut u8,
+    _len: usize,
+) -> Result<(), getrandom_03::Error> {
+    Err(getrandom_03::Error::UNSUPPORTED)
+}
diff --git a/whats_left.py b/whats_left.py
index 4f087f89af..30b1de088e 100755
--- a/whats_left.py
+++ b/whats_left.py
@@ -35,8 +35,8 @@
 implementation = platform.python_implementation()
 if implementation != "CPython":
     sys.exit(f"whats_left.py must be run under CPython, got {implementation} instead")
-if sys.version_info[:2] < (3, 12):
-    sys.exit(f"whats_left.py must be run under CPython 3.12 or newer, got {implementation} {sys.version} instead")
+if sys.version_info[:2] < (3, 13):
+    sys.exit(f"whats_left.py must be run under CPython 3.13 or newer, got {implementation} {sys.version} instead")
 
 def parse_args():
     parser = argparse.ArgumentParser(description="Process some integers.")