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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def remove_callback(self, name, before=None, after=None):
 """Remove a beforeback, and afterback pair from this Spectator If ``before`` and ``after`` are None then all callbacks for the given method will be removed. Otherwise, only the exact callback pair will be removed. Parameters name: str The name of the method the callback pair is associated with. before: None or callable The beforeback that was originally registered to the given method. after: None or callable The afterback that was originally registered to the given method. """

        if isinstance(name, (list, tuple)):
            for name in name:
                self.remove_callback(name, before, after)
        elif before is None and after is None:
            del self._callback_registry[name]
        else:
            if name in self._callback_registry:
                callback_list = self._callback_registry[name]
            else:
                callback_list = []
                self._callback_registry[name] = callback_list
            callback_list.remove((before, after))
            if len(callback_list) == 0:
                # cleanup if all callbacks are gone
                del self._callback_registry[name]