To bind application that needs the 'app' object to init
        :param app: callable function that will receive 'Flask.app' as first arg

def bind_(cls, kls):
        """
        To bind application that needs the 'app' object to init
        :param app: callable function that will receive 'Flask.app' as first arg
        """
        if not hasattr(kls, "__call__"):
            raise TypeError("From Pylot.bind_: '%s' is not callable" % kls)
        cls._bind.add(kls)
        return kls