code: def is_last_stage(self):
      return (
          self.pp_rank % self.actual_stage_num
      ) == self.actual_stage_num - 1
  
imports: import threading
  from typing import Callable, Dict, List
  import torch
  from torch._C._distributed_rpc import PyRRef
  from torch.futures import Future
  from colossalai.legacy.pipeline.pipeline_process_group import ppg
  from colossalai.legacy.pipeline.rpc._pipeline_base import Phase, PipelineEngineBase, UniqueKey, WorkerBase, WorkItem
label_desc: Use image node_id 6 for calling the ChimeraWorker obj's underlying member method code with example usage: obj.is_last_stage() and returns: unknown