```py Foo = int | str foo: object isinstance(foo, Foo) # error isinstance(foo, int | str) # no error ``` https://mypy-play.net/?mypy=master&python=3.10&gist=da37bef9ace54d59c18631a0a9f5bef2
https://mypy-play.net/?mypy=master&python=3.10&gist=da37bef9ace54d59c18631a0a9f5bef2