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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 _basic_cancel_notify(self, args):
 """Consumer cancelled by server. Most likely the queue was deleted. """

        consumer_tag = args.read_shortstr()
        callback = self._on_cancel(consumer_tag)
        if callback:
            callback(consumer_tag)
        else:
            raise ConsumerCancelled(consumer_tag, (60, 30))