fix quiz

apps/quiz/serializers/quiz.py

@@ -1,7 +1,7 @@
 from rest_framework import serializers
 
 from apps.quiz.models import Question, Quiz, QuizParticipant
-from apps.course.models import Lesson
+from apps.course.models import Lesson, Participant
 
 
 
@@ -22,10 +22,19 @@ class QuizListSerializer(serializers.ModelSerializer):
             return False 
         # Check if the user has participated in this quiz
         user = request.user
+        course = obj.lesson.course 
+           
+        if not self._is_participant(user, course):
+            return False
+        
         participated = QuizParticipant.objects.filter(user=user, quiz=obj).exists()
         return not participated
 
 
+    def _is_participant(self, student, course):
+        """Helper method to check if a student is a participant in the given course."""
+        return Participant.objects.filter(student=student, course=course).exists()
+