[Python-checkins] gh-103193: Micro-optimise helper functions for `inspect.getattr_static` (#103195)

[AlexWaygood]

https://github.com/python/cpython/commit/264c00a1c512a9bd58f47c80e72e436c639763c8
commit: 264c00a1c512a9bd58f47c80e72e436c639763c8
branch: main
author: Alex Waygood <Alex.Waygood at Gmail.com>
committer: AlexWaygood <Alex.Waygood at Gmail.com>
date: 2023-04-05T08:27:01+01:00
summary:

gh-103193: Micro-optimise helper functions for `inspect.getattr_static` (#103195)

files:
A Misc/NEWS.d/next/Library/2023-04-02-17-51-08.gh-issue-103193.xrZbM1.rst
M Lib/inspect.py

diff --git a/Lib/inspect.py b/Lib/inspect.py
index 0eceaaf9a24f..8739c9c25726 100644
--- a/Lib/inspect.py
+++ b/Lib/inspect.py
@@ -1772,9 +1772,9 @@ def trace(context=1):
 # ------------------------------------------------ static version of getattr
 
 _sentinel = object()
+_static_getmro = type.__dict__['__mro__'].__get__
+_get_dunder_dict_of_class = type.__dict__["__dict__"].__get__
 
-def _static_getmro(klass):
-    return type.__dict__['__mro__'].__get__(klass)
 
 def _check_instance(obj, attr):
     instance_dict = {}
@@ -1802,10 +1802,9 @@ def _is_type(obj):
     return True
 
 def _shadowed_dict(klass):
-    dict_attr = type.__dict__["__dict__"]
     for entry in _static_getmro(klass):
         try:
-            class_dict = dict_attr.__get__(entry)["__dict__"]
+            class_dict = _get_dunder_dict_of_class(entry)["__dict__"]
         except KeyError:
             pass
         else:
diff --git a/Misc/NEWS.d/next/Library/2023-04-02-17-51-08.gh-issue-103193.xrZbM1.rst b/Misc/NEWS.d/next/Library/2023-04-02-17-51-08.gh-issue-103193.xrZbM1.rst
new file mode 100644
index 000000000000..f0b76a605a56
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-04-02-17-51-08.gh-issue-103193.xrZbM1.rst
@@ -0,0 +1,2 @@
+Improve performance of :func:`inspect.getattr_static`. Patch by Alex
+Waygood.