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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(self, consumer_tag, nowait=False):
 """End a queue consumer This method cancels a consumer. This does not affect already delivered messages, but it does mean the server will not send any more messages for that consumer. The client may receive an abitrary number of messages in between sending the cancel method and receiving the cancel-ok reply. RULE: If the queue no longer exists when the client sends a cancel command, or the consumer has been cancelled for other reasons, this command has no effect. PARAMETERS: consumer_tag: shortstr consumer tag Identifier for the consumer, valid within the current connection. RULE: The consumer tag is valid only within the channel from which the consumer was created. I.e. a client MUST NOT create a consumer in one channel and then use it in another. nowait: boolean do not send a reply method If set, the server will not respond to the method. The client should not wait for a reply method. If the server could not complete the method it will raise a channel or connection exception. """

        if self.connection is not None:
            self.no_ack_consumers.discard(consumer_tag)
            args = AMQPWriter()
            args.write_shortstr(consumer_tag)
            args.write_bit(nowait)
            self._send_method((60, 30), args)
            return self.wait(allowed_methods=[
                (60, 31),  # Channel.basic_cancel_ok
            ])