I'd like to call this guy, vim-guy! since 2014 that I know! he has been using vim and never, not a single time, used a presentation of anykind! he live codes every single talk! and I love it!
My approach to this problem would be class Base: def foo(self): return self.bar() # noqa def __init_subclass__(cls, **kwargs): assert hasattr(cls, "bar"), "bar() method missing"