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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_publish(self, msg, exchange='', routing_key='', mandatory=False, immediate=False):
 """Publish a message This method publishes a message to a specific exchange. The message will be routed to queues as defined by the exchange configuration and distributed to any active consumers when the transaction, if any, is committed. PARAMETERS: exchange: shortstr Specifies the name of the exchange to publish to. The exchange name can be empty, meaning the default exchange. If the exchange name is specified, and that exchange does not exist, the server will raise a channel exception. RULE: The server MUST accept a blank exchange name to mean the default exchange. RULE: The exchange MAY refuse basic content in which case it MUST raise a channel exception with reply code 540 (not implemented). routing_key: shortstr Message routing key Specifies the routing key for the message. The routing key is used for routing messages depending on the exchange configuration. mandatory: boolean indicate mandatory routing This flag tells the server how to react if the message cannot be routed to a queue. If this flag is True, the server will return an unroutable message with a Return method. If this flag is False, the server silently drops the message. RULE: The server SHOULD implement the mandatory flag. immediate: boolean request immediate delivery This flag tells the server how to react if the message cannot be routed to a queue consumer immediately. If this flag is set, the server will return an undeliverable message with a Return method. If this flag is zero, the server will queue the message, but with no guarantee that it will ever be consumed. RULE: The server SHOULD implement the immediate flag. """

        args = AMQPWriter()
        args.write_short(0)
        args.write_shortstr(exchange)
        args.write_shortstr(routing_key)
        args.write_bit(mandatory)
        args.write_bit(immediate)

        self._send_method((60, 40), args, msg)