Update how-to-sign-in-with-metamask-python-django.md

Tutorial edits as a companion to the pull request proposed [here](MoralisWeb3/demo-apps#71)

docs/03-authentication-api/tutorials/how-to-sign-in-with-metamask-python-django.md

@@ -106,6 +106,7 @@ from django.shortcuts import render, redirect
 from django.http import HttpResponse, JsonResponse
 from django.contrib.auth import authenticate, login
 from django.contrib.auth.models import User
+from datetime import datetime, timedelta, timezone
 
 API_KEY = 'WEB3_API_KEY_HERE'
 # this is a check to make sure the the API key was set
@@ -126,14 +127,21 @@ def request_message(request):
     data = json.loads(request.body)
     print(data)
 
+    #setting request expiration time to 1 minute after the present->
+    present = datetime.now(timezone.utc)
+    present_plus_one_m = present + timedelta(minutes=1)
+    expirationTime = str(present_plus_one_m.isoformat())
+    expirationTime = str(expirationTime[:-6]) + 'Z'
+    print(f'ExpirationTime = {expirationTime}')
+
     REQUEST_URL = 'https://authapi.moralis.io/challenge/request/evm'
     request_object = {
       "domain": "defi.finance",
       "chainId": 1,
       "address": data['address'],
       "statement": "Please confirm",
       "uri": "https://defi.finance/",
-      "expirationTime": "2023-01-01T00:00:00.000Z",
+      "expirationTime": expirationTime,
       "notBefore": "2020-01-01T00:00:00.000Z",
       "timeout": 15
     }
@@ -356,4 +364,4 @@ After the message is signed and the authentication is successful, you can see th
 
 ![](/img/content/0a87357-profile_info_1.webp)
 
-![User Profile Page](/img/content/03f26e6-profile_info_3.webp)
+![User Profile Page](/img/content/03f26e6-profile_info_3.webp)