[issue44653] Parameter substitution in the union type does not work with typing.Union

[Serhiy Storchaka]

Change by Serhiy Storchaka <storchaka+cpython at gmail.com>:


----------
pull_requests:  -25757

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue44653>
_______________________________________