code: def from_json(cls, json):
      
      obj = cls(property_range.PropertyRange.from_json(json["property_range"]),
                namespace_range.NamespaceRange.from_json_object(json["ns_range"]),
                model.QuerySpec.from_json(json["query_spec"]))
      cursor = json["cursor"]
      # lint bug. Class method can access protected fields.
      # pylint: disable=protected-access
      if cursor and json["cursor_object"]:
        obj._cursor = datastore_query.Cursor.from_websafe_string(cursor)
      else:
        obj._cursor = cursor
      return obj
docs: Inherit doc.