Original code copyright (C) 2009-2022 Rudolf Cardinal (

This file is part of cardinal_pythonlib.

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Support functions to do with metaclasses. IGNORE; NOT WORKING PROPERLY.

class cardinal_pythonlib.metaclasses.CooperativeMeta(name: str, bases: Tuple[Type, ...], members: Dict[str, Any])[source]

The idea is to use this as the metaclass for a class Derived that inherits from bases BaseOne, BaseTwo, …, whose metaclasses are not of the same type.

This should avoid the error:

TypeError: metaclass conflict: the metaclass of a derived class must
be a (non-strict) subclass of the metaclasses of all its bases

Code from:

See also:

HOWEVER, it’s not actually working. Does Python 3 have stricter checking than Python 2?

See also

class cardinal_pythonlib.metaclasses.DebuggingCooperativeMeta(name: str, bases: Tuple[Type, ...], members: Dict[str, Any])[source]

CooperativeMeta, but with print() output. Still not working.