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

def send_durable_exchange_message(self, exchange_name, body):
        """
        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
        """
        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