code: def commit(self, tag):
      # nebula commit will be call when all files under give tag are ready to be persisted in the async way.
      logger.info(
          f"[Nebula] all files for {tag} are saved in tier1. It is ready to start persisting"
      )
      commit_rls = self.checkpoint.commit()
      if not commit_rls:
          logger.error(
              f"[Nebula] failed to commit the checkpoint, please check the log."
          )
          return False
      return commit_rls
  
file_path: deepspeed/deepspeed/runtime/checkpoint_engine/nebula_checkpoint_engine.py
imports: import os
  import torch
  import torch_nebula
  from deepspeed.runtime.checkpoint_engine.checkpoint_engine import CheckpointEngine
  from deepspeed.utils import logger, log_dist
  from deepspeed.nebula.constants import *
label_desc: Use image node_id 5 for calling the NebulaCheckpointEngine obj's underlying member method code with example usage: obj.commit(tag) and returns: commit_rls, False