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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, msg, exchange, routing_key, mandatory=False,
                immediate=False, ticket=None):
        '''
        publish a message.
        '''
        args = Writer()
        args.write_short(ticket or self.default_ticket).\
            write_shortstr(exchange).\
            write_shortstr(routing_key).\
            write_bits(mandatory, immediate)

        self.send_frame(MethodFrame(self.channel_id, 60, 40, args))
        self.send_frame(
            HeaderFrame(self.channel_id, 60, 0, len(msg), msg.properties))

        f_max = self.channel.connection.frame_max
        for f in ContentFrame.create_frames(self.channel_id, msg.body, f_max):
            self.send_frame(f)