code: def as_rack_controller(self):
          
          if self.node_type not in [
                  NodeType.RACK_CONTROLLER, NodeType.REGION_AND_RACK_CONTROLLER]:
              raise ValueError(
                  'Cannot convert to `RackController`, node_type is not a '
                  'rack controller.')
          return self._origin.RackController(self._data)
docs: Convert to a `RackController` object.
  
          `node_type` must be `NodeType.RACK_CONTROLLER` or
          `NodeType.REGION_AND_RACK_CONTROLLER`.