How to print out multiple responses from service

edit

Hello, I'm currently trying to create a service which can send multiple responses. I edited the tutorial service ( http://wiki.ros.org/ROS/Tutorials/Wri... ) to:

int64 a
int64 b
---
int64 sum
int64 multi

multi = a * b

in another question (https://answers.ros.org/question/3812...) somebody already helped me to adjust the server.py but so far I'm not able to print out sum and multi this is my attempt so far client.py:

#!/usr/bin/env python

from __future__ import print_function

import sys
import rospy
from service_node.srv import *

def add_two_ints_client(x, y):
    rospy.wait_for_service('add_two_ints')
    try:
        add_two_ints = rospy.ServiceProxy('add_two_ints', AddTwoInts)
        resp1 = add_two_ints(x, y)
        return resp1
    except rospy.ServiceException as e:
        print("Service call failed: %s"%e)

def usage():
    return "%s [x y]"%sys.argv[0]

if __name__ == "__main__":
    if len(sys.argv) == 3:
        x = int(sys.argv[1])
        y = int(sys.argv[2])
    else:
        print(usage())
        sys.exit(1)
    print("Requesting %s+%s"%(x, y))
    resp = add_two_ints_client(x, y)
    print(resp)

server.py:

#!/usr/bin/env python

from __future__ import print_function

from service_node.srv import AddTwoInts,AddTwoIntsResponse
import rospy

def handle_add_two_ints(req):
    print("Returning [%s + %s = %s]"%(req.a, req.b, (req.a + req.b)))
    return AddTwoIntsResponse(sum(req.a + req.b), multi=(req.a * req.b))

def add_two_ints_server():
    rospy.init_node('add_two_ints_server')
    s = rospy.Service('add_two_ints', AddTwoInts, handle_add_two_ints)
    print("Ready to add two ints.")
    rospy.spin()

if __name__ == "__main__":
    add_two_ints_server()

output:

Requesting 5+1
Service call failed: service [/add_two_ints] responded with an error: b"error processing request: 'int' object is not iterable"
None

System: ROS noetic, Ubuntu 20.04, Python 3

Traceback from the server:
[ERROR] [1624971980.654584]: Error processing request: multi is not an attribute of AddTwoIntsResponse
['Traceback (most recent call last):\n', '  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_service.py", line 632, in _handle_request\n    response = convert_return_to_response(self.handler(request), self.response_class)\n', '  File "/home/fabi/catkin_ws/src/service_node/scripts/server.py", line 10, in handle_add_two_ints\n    return AddTwoIntsResponse(sum=(req.a + req.b), multi=(req.a * req.b))\n', '  File "/home/fabi/catkin_ws/devel/lib/python3/dist-packages/service_node/srv/_AddTwoInts.py", line 154, in __init__\n    super(AddTwoIntsResponse, self).__init__(*args, **kwds)\n', '  File "/opt/ros/noetic/lib/python3/dist-packages/genpy/message.py", line 361, in __init__\n    raise AttributeError(\'%s is not an attribute of %s\' % (k, self.__class__.__name__))\n', 'AttributeError: multi is not an attribute of AddTwoIntsResponse\n']