code: def check_shell(cmd, shell=None):
      
      if isinstance(shell, bool):
          return shell
      return "|" in cmd or ">" in cmd or r"*" in cmd
docs: Determine whether a command appears to involve shell process(es).
      The shell argument can be used to override the result of the check.
  
      :param str cmd: Command to investigate.
      :param bool shell: override the result of the check with this value.
      :return bool: Whether the command appears to involve shell process(es).