code: def run_subprocess(
      self, target, args=..., nprocs=1, envs=None
  ) -> Any:
      import cloudpickle
      import subprocess
      import sys
  
      with TemporaryDirectory() as temp_dir:
          with open(os.path.join(temp_dir, "args.pkl"), "wb") as f:
              cloudpickle.dump(args, f)
          with open(os.path.join(temp_dir, "target.pkl"), "wb") as f:
              cloudpickle.dump(target, f)
  
          ex_list = []
          cwd_path = os.path.dirname(__file__)
          for i in range(nprocs):
              for key, val in os.environ.items():
                  if key not in envs[i]:
                      envs[i][key] = val
              if "OMP_NUM_THREADS" in envs[i]:
                  set_op_thread = envs[i]["OMP_NUM_THREADS"]
              else:
                  # 0 means the system picks an appropriate number
                  set_op_thread = "0"
              ex_list.append(
                  subprocess.Popen(
                      [
                          sys.executable,
                          f"{cwd_path}/subprocess_worker.py",
                          temp_dir,
                          set_op_thread,
                      ],
                      env=envs[i],
                  )
              )
          for _, ex in enumerate(ex_list):
              ex.wait()
  
          results = []
          for i in range(nprocs):
              with open(
                  os.path.join(temp_dir, f"history_{i}"), "rb"
              ) as f:
                  results.append(cloudpickle.load(f))
      return results
  
file_path: BigDL/python/nano/src/bigdl/nano/utils/tf/backend.py
imports: import os
  from tempfile import TemporaryDirectory
  from typing import Any
  from bigdl.nano.utils.common import Backend
  from bigdl.nano.utils.common import invalidInputError
label_desc: Use image node_id 4 for calling the MultiprocessingBackend obj's underlying member method code with example usage: obj.run_subprocess(target, args, nprocs, envs) and returns: results