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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 publish(self, message, routing_key, *, mandatory=True):
 """ Publish a message on the exchange, to be asynchronously delivered to queues. :param asynqp.Message message: the message to send :param str routing_key: the routing key with which to publish the message :param bool mandatory: if True (the default) undeliverable messages result in an error (see also :meth:`Channel.set_return_handler`) """

        self.sender.send_BasicPublish(self.name, routing_key, mandatory, message)