diff --git a/flashcards/serializers.py b/flashcards/serializers.py
index e36527e..9968fa7 100644
--- a/flashcards/serializers.py
+++ b/flashcards/serializers.py
@@ -99,7 +99,7 @@ class MaskFieldSerializer(serializers.Field):
     }
 
     def to_representation(self, value):
-        return dumps(list(self._make_mask(value)))
+        return map(list, self._make_mask(value))
 
     def to_internal_value(self, value):
         if not isinstance(value, list):
diff --git a/flashcards/views.py b/flashcards/views.py
index fb1194a..816f163 100644
--- a/flashcards/views.py
+++ b/flashcards/views.py
@@ -18,10 +18,12 @@ from rest_framework.viewsets import ReadOnlyModelViewSet, GenericViewSet
 from django.core.mail import send_mail
 from django.contrib.auth import authenticate
 from django.contrib.auth.tokens import default_token_generator
+from django.db.models import Count, F
 from rest_framework.status import HTTP_204_NO_CONTENT, HTTP_201_CREATED, HTTP_200_OK
 from rest_framework.response import Response
 from rest_framework.exceptions import AuthenticationFailed, NotAuthenticated, ValidationError, PermissionDenied
 from simple_email_confirmation import EmailAddress
+from math import e
 
 
 class SectionViewSet(ReadOnlyModelViewSet):
@@ -374,7 +376,16 @@ class UserFlashcardQuizViewSet(GenericViewSet, CreateModelMixin, UpdateModelMixi
             raise ValidationError("No matching flashcard found in your decks")
 
         user_flashcard = user_flashcard_filter.order_by('?').first()
-        # user_flashcard = user_flashcard_filter.annotate(spaced=F())
+        """
+        user_flashcard_pks = user_flashcard_filter.values('pk')
+        quiz_filter = UserFlashcardQuiz.filter(
+            user_flashcard__in=user_flashcard_pks
+        ).annotate(
+            revise_count=Count('user_flashcard')
+        ).annotate(
+
+        )
+        """
         mask = user_flashcard.get_mask().get_random_blank()
         user_flashcard_quiz = UserFlashcardQuiz(user_flashcard=user_flashcard,
                                                 blanked_word=user_flashcard.flashcard.text[slice(*mask)])