test.support.os_support.can_chmod() tests for hasattr(os, "chown") instead of hasattr(os, "chmod"). This, and also the fact that it tests bits not supported on Windows, makes it always returning False on Windows. It may make some meaningful tests skipped on Windows and prevents of using it in new tests for os.chmod().

Linked PRs

• gh-113090: Fix test.support.os_support.can_chmod() on Windows #113091
• [3.12] gh-113090: Fix test.support.os_support.can_chmod() on Windows (GH-113091) #113099
• [3.11] gh-113090: Fix test.support.os_support.can_chmod() on Windows (GH-113091) #113100