[3.12] gh-125783: Add tests to prevent regressions with the combination of ctypes and metaclasses. (GH-125881)

[miss-islington]

(cherry picked from commit 1384409)

Co-authored-by: Jun Komoda 45822440+junkmd@users.noreply.github.com

• Issue: Add tests to prevent regressions with the combination of ctypes and metaclasses. #125783

[junkmd]

Unlike main and 3.13, 3.12 does not yet include the test_ctypes._support module, which is causing test failures.

I think a maintainer with the appropriate permissions needs to do such as git checkout 1384409 -- Lib/test/test_ctypes/_support.py on this branch.

[encukou]

I'll try backporting all of #113727.

[encukou]

Nope, too invasive. I'll add _support.py as suggested. If we backport the whole commit later, _support.py shouldn't conflict with it.