Connect to queue_name, post a durable message with body, disconnect from queue_name.
        :param queue_name: str: name of the queue we want to put a message on
        :param body: content of the message we want to send

def send_durable_message(self, queue_name, body):
        """
        Connect to queue_name, post a durable message with body, disconnect from queue_name.
        :param queue_name: str: name of the queue we want to put a message on
        :param body: content of the message we want to send
        """
        self.connect()
        channel = self.create_channel(queue_name)
        channel.basic_publish(exchange='',
                              routing_key=queue_name,
                              body=body,
                              properties=pika.BasicProperties(
                                 delivery_mode=2,  # make message persistent
                              ))
        self.close()