A dict subclass which does not override __getitem__ (like collections.Counter) should have Dict_Type.tp_as_mapping->mp_subscript as its Py_TYPE(lhs)->tp_as_mapping->mp_subscript, but they are not the same.

CC @ericsnowcurrently .

Linked PRs

• gh-132284: Don't wrap base PyCFunction slots on class creation if not overridden #132329