code: def _parse_hostfile(hostfile_lines):
      # Regex matches one or more non-whitespace characters (\S+) at the start of
      # the line, followed by one or more whitespace characters (\s+), followed
      # by the string "slots=", followed by one or more digits (\d+).
      pattern = r"^(\S+)\s+slots=(\d+)"
  
      resource_pool = collections.OrderedDict()
  
      for line in hostfile_lines:
          line = line.strip()
          match = re.search(pattern, line)
          if line.startswith("#") or line == "":
              # hostfile comment or empty line, ignore
              continue
          elif match:
              host = match.group(1)
              num_slots = int(match.group(2))
              if host in resource_pool:
                  logger.error(f"Bad hostfile text: {hostfile_lines}")
                  raise ValueError(
                      f"Hostfile contains multiple entries for {host}, unable to proceed with launching"
                  )
              resource_pool[host] = num_slots
          else:
              logger.error(f"Bad hostfile text: {hostfile_lines}")
              raise ValueError(
                  f"Hostfile contains a bad entry: {line}, unable to proceed with launching"
              )
  
      if len(resource_pool) == 0:
          logger.error(f"Bad hostfile text: {hostfile_lines}")
          raise ValueError(
              "Hostfile is empty or not formatted correctly, unable to proceed with launching."
          )
  
      return resource_pool
  
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 3 for calling a global function with example usage: _parse_hostfile(hostfile_lines) and returns: resource_pool