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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 nack(self, delivery_tag, multiple=False, requeue=False):
        '''Send a nack to the broker.'''
        args = Writer()
        args.write_longlong(delivery_tag).\
            write_bits(multiple, requeue)

        self.send_frame(MethodFrame(self.channel_id, 60, 120, args))