code: def ls(directory, long_format, recursive):
      
      # List each file/directory on a separate line.
      board_files = files.Files(_board)
      for f in board_files.ls(directory, long_format=long_format, recursive=recursive):
          print(f)
docs: List contents of a directory on the board.
  
      Can pass an optional argument which is the path to the directory.  The
      default is to list the contents of the root, /, path.
  
      For example to list the contents of the root run:
  
        ampy --port /board/serial/port ls
  
      Or to list the contents of the /foo/bar directory on the board run:
  
        ampy --port /board/serial/port ls /foo/bar
  
      Add the -l or --long_format flag to print the size of files (however note
      MicroPython does not calculate the size of folders and will show 0 bytes):
  
        ampy --port /board/serial/port ls -l /foo/bar