Django Prefetch not fetching the related fields - django

Question

I have four models that reference a CustomUser table.
class Profile(models.Model):
user = models.OneToOneField(CustomUser, on_delete=models.CASCADE)
...
class Question(models.Model):
question = models.CharField(max_length=140)
class Answer(models.Model):
question = models.ForeignKey(Question, on_delete=models.CASCADE, related_name='answers')
answer = models.CharField(max_length=70)
class Response(models.Model):
user = models.ForeignKey(CustomUser, on_delete=models.CASCADE, related_name='responses')
question = models.ForeignKey(Question, on_delete=models.CASCADE)
answer = models.ForeignKey(Answer, on_delete=models.CASCADE)
Each question has multiple answers but each user can only pick one answer to each question.
Each user can answer multiple questions.
I have a ViewSet that authenticated users can access that is supposed to return a list of users with the same answers as them.
serializer_class = serializers.ProfileSerializer
def get_queryset(self):
user_answers = qmodels.Answer.objects.filter(response__user=self.request.user)
return models.Profile.objects.prefetch_related(
Prefetch(
'user__responses',
queryset=qmodels.Response.objects.filter(answer__in=user_answers),
to_attr='common_answers'
)
)
class ProfileSerializer(serializers.ModelSerializer):
common_answers = ResponseSerializer(many=True)
However, I'm getting the following error:
Got AttributeError when attempting to get a value for field `common_answers` on serializer `ProfileSerializer`.
The serializer field might be named incorrectly and not match any attribute or key on the `Profile` instance.
Original exception text was: 'Profile' object has no attribute 'common_answers'.
I've added a print after prefetch_related and it is showing the base records properly but there is no common_answers field