PR gh-93627: Align copy module behaviour with pickle module aligns the behaviour of the copy and pickle modules for classes that set methods like __copy__ or __reduce_ex__ to None. The difference in behaviour has existed for a long time and does not seem to cause problems, but the corresponding issue is blocking another PR gh-72793: C implementation of parts of copy.deepcopy. It would be nice to either fix the corresponding issue, or decide to accept the (small) difference in behavior.