Nested Lists endpoints within DRF viewsets

nested_lists.py

class NestedListMixin(object):
    def get_nested_list(self, queryset, serializer_class):
        """
        List view in function form.
        First argument can be a list or a queryset.
        """
        page = self.paginate_queryset(queryset)

        if page is not None:
            serializer = serializer_class(page, many=True,
                                          context=self.get_serializer_context())
            return self.get_paginated_response(serializer.data)

        serializer = serializer_class(queryset, many=True)
        return Response(serializer.data)

    def get_filtered_nested_list(self, queryset, serializer_class, extra_view_attributes=None):
        """
        List view in function form.
        First argument must be queryset for correct filtering.
        """
        if extra_view_attributes is None:
            extra_view_attributes = {}
        extra_view_attributes.setdefault('serializer_class', serializer_class)

        view_class = type('NestedView', (object,), extra_view_attributes)

        # Usually defined in GenericAPIView.filter_queryset
        # Re-written here to override the passed view.
        for backend in list(self.filter_backends):
            queryset = backend().filter_queryset(self.request, queryset, view_class())

        return self.get_nested_list(queryset, serializer_class)

# Usage: 
class VendorViewSet(NestedListMixin, viewsets.ModelViewSet):
    #...
    @detail_route(methods=['get'])
    def requirements(self, request, pk=None):
        queryset = self.get_object().vendorrequirement_set.all()
        return self.get_filtered_nested_list(queryset, serializers.VendorRequirementSerializer)