  
      def __init__(self):
          assert django_filters, 'Using DjangoFilterBackend, but django-filter is not installed'
  
      def get_filter_class(self, view):
          """
          Return the django-filters `FilterSet` used to filter the queryset.
          """
          filter_class = getattr(view, 'filter_class', None)
          filter_fields = getattr(view, 'filter_fields', None)
 
</s> remove         model_cls = getattr(view, 'model', None)
        queryset = getattr(view, 'queryset', None)
        if model_cls is None and queryset is not None:
            model_cls = queryset.model
 </s> add  </s> remove         filter_class = self.get_filter_class(view)
 </s> add         filter_class = self.get_filter_class(view, queryset) </s> remove             assert model_cls is not None, 'Cannot use DjangoFilterBackend ' \
                'on a view which does not have a .model or .queryset attribute.'

 </s> add 
    def get_filter_class(self, view, queryset=None):
  
      def __init__(self):
          assert django_filters, 'Using DjangoFilterBackend, but django-filter is not installed'
  
    def get_filter_class(self, view, queryset=None):
          """
          Return the django-filters `FilterSet` used to filter the queryset.
          """
          filter_class = getattr(view, 'filter_class', None)
          filter_fields = getattr(view, 'filter_fields', None)
keep keep keep keep replace keep keep keep keep keep
 Base automatic filterset model on the queryset model.  Fixes #834. 
rest_framework/filters.py