code: def find_nodes(self, **kwargs):
          
          filter_args = {}
          classname = self.data_content_type.model_class().__name__.lower()
          for key, value in kwargs.items():
              filter_args['%s__%s' % (classname, key)] = value
  
          return Node.objects.filter(**filter_args)
docs: Searches the data nodes that are associated with this graph using
          the key word arguments as a filter and returns a
          :class:`django.db.models.query.QuerySet`` of the attached
          :class:`Node` objects.
  
          :param kwargs: 
              filter arguments applied to searching the :class:`BaseNodeData`
              subclass associated with this graph.
          :returns: 
              ``QuerySet`` of :class:`Node` objects