Python 3 Patterns & Idioms / code / Metaclasses /

# Metaclasses/
# Combining the steps for metaclass creation in Python 2.x

class Simple2(object):
    class __metaclass__(type):
        def __init__(cls, name, bases, nmspc):
            # This won't work:
            # super(__metaclass__, cls).__init__(name, bases, nmspc)
            # Less-flexible specific call:
            type.__init__(cls, name, bases, nmspc)
            cls.uses_metaclass = lambda self : "Yes!"

class Simple3(Simple2): pass
simple = Simple3()
print simple.uses_metaclass()

""" Output:
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