Importing inspect is expensive. Defer it unless needed.

jaraco · jaraco · commit 15312a7bce32 · 2021-03-14T10:13:19.000-04:00
diff --git a/importlib_metadata/__init__.py b/importlib_metadata/__init__.py
@@ -5,7 +5,6 @@
 import sys
 import zipp
 import email
-import inspect
 import pathlib
 import operator
 import warnings
@@ -206,6 +205,8 @@ def _from_text_for(cls, text, dist):
 
 
 def flake8_bypass(func):
+    # defer inspect import as performance optimization.
+    import inspect
     is_flake8 = any('flake8' in str(frame.filename) for frame in inspect.stack()[:5])
     return func if not is_flake8 else lambda: None
 
