__class__ of a __class__ check worked only by chance.
diff --git a/Lib/test/test_cfgparser.py b/Lib/test/test_cfgparser.py
index a712b2b..1db9217 100644
--- a/Lib/test/test_cfgparser.py
+++ b/Lib/test/test_cfgparser.py
@@ -993,7 +993,7 @@
cf.add_section(123)
cf.set(123, 'this is sick', True)
self.assertEqual(cf.get(123, 'this is sick'), True)
- if cf._dict.__class__ is configparser._default_dict:
+ if cf._dict is configparser._default_dict:
# would not work for SortedDict; only checking for the most common
# default dictionary (OrderedDict)
cf.optionxform = lambda x: x