[Python-ideas] Allow metaclass to override __subclasscheck__ for metaclass relations

I would like this code to work, but currently python ignores __subclasscheck__ in many places where it checks for subclasses: class MM(type):     def __subclasscheck__(self, subclass):         return issubclass(subclass, type) class M(type, metaclass=MM):     pass class N(type):     pass class C(metaclass=M):     pass class D(metaclass=N):     pass class E(C, D, metaclass=N):     pass def main():     e = E() main()