code: def unix2dos_dir(dir_name):
      modified_files = []
      os.path.walk(dir_name, unix2dos_one_dir, modified_files)
      return modified_files
  
imports: from __future__ import division, absolute_import, print_function
  import sys, re, os
label_desc: Use image node_id 6 for calling a global function with example usage: unix2dos_dir(dir_name) and returns: modified_files