code: def get_hosts_from_file(filename):
      with open(filename) as f:
          tmp = f.readlines()
      assert len(tmp) > 0
      hosts = []
      for h in tmp:
          if len(h.strip()) > 0:
              # parse addresses of the form ip:port
              h = h.strip()
              i = h.find(":")
              p = "22"
              if i != -1:
                  p = h[i + 1 :]
                  h = h[:i]
              # hosts now contain the pair ip, port
              hosts.append((h, p))
      return hosts
  
file_path: byteps/launcher/dist_launcher.py
imports: import argparse
  import os, sys
  import signal
  import logging
  import subprocess
  from multiprocessing import Pool, Process
  from threading import Thread
label_desc: Use image node_id 3 for calling a global function with example usage: get_hosts_from_file(filename) and returns: hosts