@classmethod
def clear_special_keys(cls, kwargs, *args):
    """
        Remove keys handled by BaseHandler that may interfere with setup().
        This should be called explicitly in setup() where required.
        """
    for special_key in cls.special_keys:
        kwargs.pop(special_key, None)
    for special_key in args:
        kwargs.pop(special_key, None)
    return kwargs
