code: def clean_process_marks():
      """delete all existing processes marks"""
      if os.name != "posix":
          return
  
      logger.debug("Deleting PIDs..")
      p = Path(tempfile.gettempdir()).joinpath("mindsdb/processes/")
      if p.exists() is False:
          return
      for path in p.iterdir():
          if path.is_dir() is False:
              return
          for file in path.iterdir():
              file.unlink()
  
file_path: mindsdb/mindsdb/utilities/fs.py
imports: import os
  import tempfile
  import threading
  import time
  from pathlib import Path
  from typing import Optional
  import psutil
  from appdirs import user_data_dir
  from mindsdb.utilities import log
label_desc: Use image node_id 9 for calling a global function with example usage: clean_process_marks() without return types