new_contents: import os
  import codecs
  import sys
  from os import path
  
  
  def rename_duplicate(top_dir, dry_run=True):
      top = path.normcase(top_dir)
      for root, _, files in os.walk(top):
          for name in files:
              base, ext = path.splitext(name)
              if not ext or ext.lower() not in ['.jpg', 'jpeg', '.tiff']:
                  continue
              print(base, ext)
              rel_path = path.join(root, name)
              src_path = path.abspath(rel_path)
              dst_name = "{}_1{}".format(base, ext)
              dst_path = path.join(root, dst_name)
              os.rename(src_path, dst_path)
              print("Rename {} to {}".format(name, dst_name))
  
  
  if __name__ == "__main__":
      dry_run = len(sys.argv) < 3 or sys.argv[2] != "-e"
      rename_duplicate(sys.argv[1], dry_run)
  
subject: add rename duplicate