new_contents: #!/usr/bin/env python3
  """
  argparse functions.
  """
  
  
  import argparse
  import os
  
  
  def dir_path(path):
      if os.path.isdir(path):
          return path
      else:
          raise argparse.ArgumentTypeError(
              f"readable_dir:{path} is not a valid path"
          )
  
subject: Add argparse functions