[issue31841] Several methods of collections.UserString do not return instances of UserString or its subclasses

[Dmitry Kazakov]

Change by Dmitry Kazakov <waultah+py at gmail.com>:


----------
keywords: +patch
pull_requests: +4438
stage:  -> patch review

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue31841>
_______________________________________