code: def _run_subprocess(tmpdir, num_processes):
      from bigdl.nano.utils.common import schedule_processors
  
      envs = schedule_processors(num_processes)
  
      processes = []
      cwd_path = os.path.split(os.path.realpath(__file__))[0]
      for i in range(num_processes):
          processes.append(
              subprocess.Popen(
                  [
                      sys.executable,
                      f"{cwd_path}/parallel_worker.py",
                      tmpdir,
                  ],
                  env=envs[i],
              )
          )
  
      return processes
  
imports: import os
  import subprocess
  import sys
  import copy
  import json
  import logging
label_desc: Use image node_id 2 for calling a global function with example usage: _run_subprocess(tmpdir, num_processes) and returns: processes