gh-74690: Make a typing test more resilient by AlexWaygood · Pull Request #104691 · python/cpython
While backporting #104622 to typing_extensions (python/typing_extensions#161), I discovered that one of the tests I added in #104622 fails on PyPy due to small differences in PyPy's implementation of abc.ABCMeta. Tests in CPython's test suite should generally be implementation-agnostic unless a test is explicitly marked with @test.support.cpython_only (or similar), so let's adapt the test so that it works equally well on alternative implementations.