code: def send_durable_exchange_message(self, exchange_name, body):
          
          self.connect()
          channel = self.connection.channel()
          # Fanout will send message to multiple subscribers
          channel.exchange_declare(exchange=exchange_name, type='fanout')
          result = channel.basic_publish(exchange=exchange_name, routing_key='', body=body,
                                         properties=pika.BasicProperties(
                                             delivery_mode=2,  # make message persistent
                                         ))
          self.close()
          return result
docs: Send a message with the specified body to an exchange.
          :param exchange_name: str: name of the exchange to send the message into
          :param body: str: contents of the message
          :return Bool: True when delivery confirmed