python - How to use the __subclasscheck__ magic method? -

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how can make class lies has subclassed?

after reading doc i've attempted this:

>>> class allyourbase(type): ...     @classmethod ...     def __subclasscheck__(cls, other): ...         return true ...      >>> class allyour(object): ...     __metaclass__ = allyourbase

now, class should report base belong him.

but didn't work:

>>> issubclass(allyour, int) false

why not?

if want allyour claim subclass of every class, isn't possible. __subclasscheck__ works in other direction.

if want allyour claim every class subclasses it, remove @classmethod decorator, , switch arguments in issubclass call. special methods define on metaclass don't need special decoration.


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