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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 send_to_queue(self, message):
 """Add a message to a maildir queue. In order to handle this, the setting 'mail.queue_path' must be provided and must point to a valid maildir. :param message: a 'Message' instance. """

        if not self.queue_delivery:
            raise RuntimeError("No queue_path provided")

        return self.queue_delivery.send(*self._message_args(message))