조회수 기능을 구현하는데 질문 상세 페이지를 불러올 때 500 에러가 생깁니다...무엇이 잘못되었는지 감이 잘 잡히지 않아 질문드립니다.

base_views.py

def detail(request, question_id):
    question = get_object_or_404(Question, pk=question_id)
    context = {'question': question}
    # 조회수
    ip = get_client_ip(request)
    cnt = QuestionCount.objects.filter(ip=ip, question=question).count()
    if cnt == 0:
        qc = QuestionCount(ip=ip, question=question)
        qc.save()
        if question.view_count:
            question.view_count += 1
        else:
            question.view_count = 1
        question.save()
    else:
        question.view_count += 1
        question.save()
    return render(request, 'pybo/question_detail.html', context)

views.py

def get_client_ip(request):
    x_forwarded_for = request.META.get('HTTP_X_FORWARDED_FOR')
    if x_forwarded_for:
        ip = x_forwarded_for.split(',')[-1].strip()
    else:
        ip = request.META.get('REMOTE_ADDR')
    return ip

models.py

class QuestionCount(models.Model):
    ip = models.CharField(max_length=30)
    question = models.ForeignKey(Question, on_delete=models.CASCADE)

    def __unicode__(self):
        return self.ip

question_detail.py

<div class="badge bg-light text-dark p-2 text-start">
                    <div class="mb-2">{{ question.author.username }}</div>
                    <div>{{ question.create_date }}</div>
                    <div class="mb-2"> 조회수: {{ question.view_count }}</div>
                </div>