fixing issue with of delete action

lms/djangoapps/instructor/views/api.py

@@ -14,6 +14,7 @@
 import random
 import re
 
+
 import dateutil
 import pytz
 import edx_api_doc_tools as apidocs
@@ -22,7 +23,7 @@
 from django.core.exceptions import MultipleObjectsReturned, ObjectDoesNotExist, PermissionDenied, ValidationError
 from django.core.validators import validate_email
 from django.db import IntegrityError, transaction
-from django.http import HttpResponse, HttpResponseBadRequest, HttpResponseForbidden, HttpResponseNotFound
+from django.http import QueryDict, HttpResponse, HttpResponseBadRequest, HttpResponseForbidden, HttpResponseNotFound
 from django.shortcuts import redirect
 from django.urls import reverse
 from django.utils.decorators import method_decorator
@@ -3335,6 +3336,7 @@ def _handle_certificate_exception(self, request, course_id, action):
         """
         Handles adding or removing certificate exceptions.
         """
+        breakpoint()
         course_key = CourseKey.from_string(course_id)
         try:
             data = request.data
@@ -3367,6 +3369,13 @@ def _get_and_validate_user(self, raw_data):
         """
         Extracts the user data from the request and validates the student.
         """
+        if isinstance(raw_data, QueryDict): # its only happening in case of delete from front-end
+            raw_data = list(raw_data.keys())[0]
+            try:
+                raw_data = json.loads(raw_data)
+            except Exception as error:  # pylint: disable=broad-except
+                return None, JsonResponse({'success': False, 'message': str(error)}, status=400)
+
         try:
             user_data = raw_data.get('user_name', '') or raw_data.get('user_email', '')
         except ValueError as error: