code: def save(self, state_dict, path: str):
      log_dist(f"[Nebula] Create dummy files for loading.")
      torch.save("", path)
  
      tag = _get_tag_from_path(path)
      partition_name = os.path.basename(path)
      logger.info(
          f"[Nebula] Saving {partition_name} under tag {tag}..."
      )
      self.checkpoint.save(partition_name, state_dict)
      logger.info(f"[Nebula] Saved {partition_name} under tag {tag}.")
      return None
  
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 3 for calling the NebulaCheckpointEngine obj's underlying member method code with example usage: obj.save(state_dict, path) and returns: None