From: Raymond Hettinger <rhettinger@users.noreply.github.com>
Date: Tue, 21 Apr 2020 23:20:52 +0000 (-0700)
Subject: bpo-40327: Improve atomicity, speed, and memory efficiency of the items() loop (GH... 
X-Git-Tag: v3.9.0a6~53
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=75bedbe2ed4119ff18a2ea86c544b3cf08a92e75;p=thirdparty%2FPython%2Fcpython.git

bpo-40327: Improve atomicity, speed, and memory efficiency of the items() loop (GH-19628)
---

diff --git a/Lib/pickle.py b/Lib/pickle.py
index d7adc162c98d..1fc8b0d26c6c 100644
--- a/Lib/pickle.py
+++ b/Lib/pickle.py
@@ -339,7 +339,7 @@ def whichmodule(obj, name):
         return module_name
     # Protect the iteration by using a list copy of sys.modules against dynamic
     # modules that trigger imports of other modules upon calls to getattr.
-    for module_name, module in list(sys.modules.items()):
+    for module_name, module in sys.modules.copy().items():
         if module_name == '__main__' or module is None:
             continue
         try: