To Delete a user in Sophos UTM9 through API python script.

I am trying the below code to delete the user with the api url given REF_AaaUseTest but i am getting the response of confirmation and how can i proceed further or how can i give further input for that response to delete the user?

import requests
import base64
import json
import time
import sys
from requests.auth import HTTPBasicAuth
from requests.packages.urllib3.exceptions import InsecureRequestWarning

def main():
       url = ("")       # - sample firewall ip
         "Accept": "application/json"
       response = requests.delete(url,verify=False, headers=headers,auth=('username','pswrd')).content.decode("utf-8")
       response = json.loads(response)
    except Exception as e:
       print("\nFailed to delete user")
       print("\nerror : ",e)
if __name__ == '__main__':


'name': "Are you sure that you want to delete the user object 'usertest'?",
'rights': '',
'attrs': ['objname'],
'Oattrs': ['class', 'type'],
'objname': 'usertest',
'del_object': '',
'ref': 'REF_AaaUseTest',
'format': "Are you sure that you want to delete the %_O object '%s'?",
'class': 'aaa',
'type': 'user',
'perms': '',
'never_hide': 0,
'fatal': 0

I tried few things but those didn't worked for me with referrals so what modifications need to be done in my code and api url ? can anyone help out of this ! A Very Thanks In Advance.