old_contents: from django.shortcuts import render
  
  # Create your views here.
  
new_contents: from django.shortcuts import render
  from rest_framework.viewsets import ModelViewSet
  
  from models import Bond
  from serializers import BondSerializer
  
  
  class BondViewSet(ModelViewSet):
      serializer_class = BondSerializer
      queryset = Bond.objects.all()
  
subject: Add BondViewSet