[issue24731] Incorrect assert in str_subtype_new

[Serhiy Storchaka]

Changes by Serhiy Storchaka <storchaka at gmail.com>:


----------
resolution:  -> fixed
stage: patch review -> resolved
status: open -> closed

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue24731>
_______________________________________