I would suggest the names SlotWrapperType and MethodWrapperType because I think they match their string representations the closest.For checking whether something is a method/function one could also use inspect.isroutine (or inspect.ismethoddescriptor), but that is inconsistent with regards to builtin and python methods:>>> import inspect>>> inspect.isroutine(object.__init__)True>>> inspect.isroutine(object().__init__)False>>> class A:...   def f(self):...     pass...>>> inspect.isroutine(A.f)True>>> inspect.isroutine(A().f)TrueMaybe a function to detect the second case is needed.