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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(self, msg, callback):
 """Remove a callback from the callback list. msg: Message template callback: Callback method to remove. If callback is None, all callbacks for the message template are removed. """

        if callback is None:
            self._dict.pop(msg, None)
        else:
            cb = self._dict.get(msg, [])
            try:
                cb.remove(callback)
            except ValueError:
                pass
            if cb:
                _LOGGER.debug('%d callbacks for message: %s', len(cb), msg)
                self.add(msg, cb, True)
            else:
                self._dict.pop(msg, None)
                _LOGGER.debug('Removed all callbacks for message: %s', msg)