code: def cluster_environment(self):
      env = LightningEnvironment()
      env.world_size = lambda: int(os.environ["WORLD_SIZE"])
      env.global_rank = lambda: int(os.environ["RANK"])
      return env
  
file_path: NeMo/nemo/utils/cloud.py
imports: import os
  from pathlib import Path
  from time import sleep
  import wget
  from pytorch_lightning.plugins.environments import LightningEnvironment
  from pytorch_lightning.strategies import DDPStrategy, StrategyRegistry
  from nemo.utils import logging
label_desc: Use image node_id 1 for calling the SageMakerDDPStrategy obj's underlying member method code with example usage: obj.cluster_environment() and returns: env