code: def fetch_hostfile(hostfile_path):
      if not os.path.isfile(hostfile_path):
          logger.warning(
              "Unable to find hostfile, will proceed with training "
              "with local resources only."
          )
          return None
  
      # e.g., worker-0 slots=16
      with open(hostfile_path, "r") as fd:
          hostfile_text = fd.readlines()
  
      return _parse_hostfile(hostfile_text)
  
imports: import os
  import re
  import sys
  import json
  import base64
  import argparse
  import subprocess
  import collections
  from copy import deepcopy
  import signal
  import time
  from .multinode_runner import PDSHRunner, OpenMPIRunner, MVAPICHRunner, SlurmRunner, MPICHRunner, IMPIRunner
  from .constants import PDSH_LAUNCHER, OPENMPI_LAUNCHER, MVAPICH_LAUNCHER, SLURM_LAUNCHER, MPICH_LAUNCHER, IMPI_LAUNCHER
  from ..constants import TORCH_DISTRIBUTED_DEFAULT_PORT
  from ..nebula.constants import NEBULA_EXPORT_ENVS
  from ..utils import logger
  from ..autotuning import Autotuner
  from deepspeed.accelerator import get_accelerator
label_desc: Use image node_id 2 for calling a global function with example usage: fetch_hostfile(hostfile_path) and returns: _parse_hostfile, None