Gateway Python file for MongoDB IoT end to end use case

gateway.py

import hashlib;
import hmac;
import datetime;
import paho.mqtt.client as mqtt
import json
import calendar
import requests

mqqt_server=#enter your mqqt server here
mqqt_port=1883

def on_connect(mqttc, obj, flags, rc):
    print("Connected with result code "+str(rc))
    client.subscribe("/iotdemo/temp")

# The callback for when a PUBLISH message is received from the server.
def on_message(client, userdata, msg):
    v=str(msg.payload.decode('utf8'))
    #string comes in as bytes so need to convert it
    sample=json.loads(v)

    t=str(sample['time'])
    t=t[1:]
    t=t[:-1]
    t=t.split(",")

    time_t=datetime.datetime(int(t[0]), int(t[1]), int(t[2]), int(t[4]), int(t[5]), int(t[6]), int(t[7]))
    timestamp_utc = calendar.timegm(time_t.timetuple())

    print('Processing sample : ' + str(sample['value']))    

    body='{ "device":"' + str(sample['device']) + '", "sample_date" : "' + time_t.strftime("%Y-%m-%d") + '", "value":"' + str(sample['value']) + '", "time":"' + repr(timestamp_utc) + '" }'
    secret = #b'Enter your MongoDB Stitch Webhook password here'
    hash = hmac.new(secret, body.encode("utf-8"), hashlib.sha256)
    url = #enter your Stitch Web API URL here
    header={"Content-Type":"application/json","X-Hook-Signature":"sha256=" + hash.hexdigest()  }
    myResponse = requests.post(url,headers=header, data=body )
    print (myResponse.status_code)


# uncomment to debug
#def on_log(mqttc, obj, level, string):
#    print(string)

print('Connecting to MQQT broker')
client = mqtt.Client()
client.on_message = on_message
client.on_connect = on_connect
#client.on_log = on_log
client.connect(mqqt_server, mqqt_port, 60)
client.loop_forever()

Thank you once again for your help.

I got some trace back information after running my code. Connection to the broker was successful and data are being sampled but the traceback is something I did not understand and don't know how to go about it. Please kindly assist. (see image below).
Thank you