Issue #26013: Added compatibility with broken protocol 2 pickles created
in old Python 3 versions (3.4.3 and lower).
diff --git a/Lib/_compat_pickle.py b/Lib/_compat_pickle.py
index 6e39d4a..c0e0443 100644
--- a/Lib/_compat_pickle.py
+++ b/Lib/_compat_pickle.py
@@ -177,6 +177,13 @@
'DocXMLRPCServer': 'xmlrpc.server',
'SimpleHTTPServer': 'http.server',
'CGIHTTPServer': 'http.server',
+ # For compatibility with broken pickles saved in old Python 3 versions
+ 'UserDict': 'collections',
+ 'UserList': 'collections',
+ 'UserString': 'collections',
+ 'whichdb': 'dbm',
+ 'StringIO': 'io',
+ 'cStringIO': 'io',
})
REVERSE_IMPORT_MAPPING.update({