actually fix it this time

generic/views.py

@@ -1588,7 +1588,7 @@ class ExamViews(View, LoginRequiredMixin):
             user_id = None
         else:
             user_id = request.user.pk
-        if self.exam_mode and not exam.check_cid_user(cid, passcode, request, user_id):
+        if exam.exam_mode and not exam.check_cid_user(cid, passcode, request, user_id):
             raise Http404("No available exam")
 
         # exam_json_cache = cache.get("{}_exam_json_{}".format(self.app_name, pk))
@@ -1649,7 +1649,7 @@ class ExamViews(View, LoginRequiredMixin):
         """
         No (file based) caching is enabled for unbased exams
         """
-        exam = get_object_or_404(self.Exam, pk=pk)
+        exam: ExamBase = get_object_or_404(self.Exam, pk=pk)
 
         if exam.exam_mode and not exam.active and not self.check_user_access(request.user, pk):
             raise Http404("No available exam")