code: def term_mp(sig_num, frame):
      """kill all child processes"""
      pid = os.getpid()
      pgid = os.getpgid(os.getpid())
      print(
          "main proc {} exit, kill process group "
          "{}".format(pid, pgid)
      )
      os.killpg(pgid, signal.SIGKILL)
      return
  
file_path: PaddleOCR/test_tipc/supplementary/data_loader.py
imports: import numpy
  from paddle.vision.datasets import Cifar100
  from paddle.vision.transforms import Normalize
  import signal
  import os
  from paddle.io import Dataset, DataLoader, DistributedBatchSampler
label_desc: Use image node_id 1 for calling a global function with example usage: term_mp(sig_num, frame) without return types