Any permissive software license (which it seems CPython's is) is broadly interchangeable with any other, and can be used with both other permissive licenses and

Any permissive software license (which it seems CPython's is) is broadly interchangeable with any other, and can be used with both other permissive licenses and copyleft licenses like the GPL. That can't happen with any license that places restrictions on what it can be used for.