#!/usr/local/bin/python2
class Hook(object):
    def pre_func(*args, **kwargs):
        pass

    def post_func(*args, **kwargs):
        pass

    def attach(self, method, instance):
        def f(*args, **kwargs):
            self.pre_func(*args, **kwargs)
            method(*args, **kwargs)
            self.post_func(*args, **kwargs)
        setattr(instance, method.__name__, f)