spacepaste

import abc
from zope.interface import Interface, classImplements
class AFoo(metaclass=abc.ABCMeta):
pass
class IFoo(Interface):
pass
classImplements(AFoo, IFoo)
class Foo(AFoo):
pass
class Bar:
pass
AFoo.register(Bar)
print('Foo extends AFoo', issubclass(Foo, AFoo))
print('Foo implements IFoo', IFoo.implementedBy(Foo))
print('Bar extends AFoo', issubclass(Bar, AFoo))
print('Bar implements IFoo', IFoo.implementedBy(Bar))