From 7e1786c284fd2ad3b2b1b2ffe0dbe375cae18b8d Mon Sep 17 00:00:00 2001
From: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Date: Thu, 26 Aug 2021 02:13:59 +0800
Subject: [PATCH] bpo-44524: Don't modify MRO when inheriting from
 typing.Annotated (GH-27841) (cherry picked from commit
 23384a1749359f0ae7aaae052073d44b59e715a1)

Co-authored-by: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
---
 Lib/test/test_typing.py | 5 +++++
 Lib/typing.py           | 7 ++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index b1cd5471256339..7b2fd698089938 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -4512,6 +4512,11 @@ def test_annotated_in_other_types(self):
         X = List[Annotated[T, 5]]
         self.assertEqual(X[int], List[Annotated[int, 5]])
 
+    def test_annotated_mro(self):
+        class X(Annotated[int, (1, 10)]): ...
+        self.assertEqual(X.__mro__, (X, int, object),
+                         "Annotated should be transparent.")
+
 
 class TypeAliasTests(BaseTestCase):
     def test_canonical_usage_with_variable_annotation(self):
diff --git a/Lib/typing.py b/Lib/typing.py
index 493546045a2bd8..423329a98005c8 100644
--- a/Lib/typing.py
+++ b/Lib/typing.py
@@ -1573,7 +1573,7 @@ def __init__(self, origin, metadata):
         if isinstance(origin, _AnnotatedAlias):
             metadata = origin.__metadata__ + metadata
             origin = origin.__origin__
-        super().__init__(origin, origin, name="Annotated")
+        super().__init__(origin, origin)
         self.__metadata__ = metadata
 
     def copy_with(self, params):
@@ -1601,6 +1601,11 @@ def __eq__(self, other):
     def __hash__(self):
         return hash((self.__origin__, self.__metadata__))
 
+    def __getattr__(self, attr):
+        if attr in {'__name__', '__qualname__'}:
+            return 'Annotated'
+        return super().__getattr__(attr)
+
 
 class Annotated:
     """Add context specific metadata to a type.