title: How to modify get_queryset result value
body: <p>I am trying to modify my get_queryset result</p>
  
  <p>Here is my my filter, view and serializer</p>
  
  <p><strong>view.py</strong></p>
  
  <pre><code> class AccountDetailFilter(filters.FilterSet):
          product_key = filters.CharFilter(name='product__product_name')
          account_name = filters.AllValuesFilter(name='account__account_key')
          service_provider_name = filters.CharFilter(name='product__service_provider__service_provider_name', )
          allocation_key = filters.CharFilter(name='account__account_allocation__allocation_key')
  
          class Meta:
              model = BillingLine
              fields = ('product_key', 'account_name', 'service_provider_name', 'allocation_key')
  
  class AccountDetailList(generics.ListAPIView):
      serializer_class = BillingSerializer
      filter_backends = (DjangoFilterBackend,)
      filter_class = AccountDetailFilter
  
  
      def get_queryset(self):
          now = datetime.datetime.now()
          start_date = self.kwargs.get('start_date_time', now)
          end_date = self.kwargs.get('end_date_time', now)
          serializer = BillingSerializer(data={'start_date': start_date, 'end_date': end_date})
          serializer.is_valid(raise_exception=True)
          queryset = BillingLine.objects.select_related().filter(start_date__gte=start_date, end_date__lte=end_date)
          queryset =  queryset.order_by('-id')
          print(queryset.count())
          return queryset
  </code></pre>
  
  <p><strong>Serializers.py</strong></p>
  
  <pre><code>class BillingSerializer(serializers.Serializer):
      id = serializers.IntegerField(read_only=True)
      start_date = serializers.DateTimeField()
      end_date = serializers.DateTimeField()
      account_key = serializers.CharField(source='account_id',required=False)
      product_key = serializers.CharField(source='product_id',required=False)
      total_amount = serializers.FloatField(required=False)
  </code></pre>
  
  <p>After retrieving the result(ie get_queryset), I need to modify/add the data in the result . Is there any way to do this . </p>
  
  <p>Also can we get the other field values to serializers from the result queryset. Because the  <code>queryset = BillingLine.objects.select_related().filter(start_date__gte=start_date, end_date__lte=end_date)</code> is returning the almost all the data (sepecifally product name which is from products table)</p>