old_contents: # -*- coding:utf-8 -*-
  import os
  import subprocess
  import sys
  import imghdr
  
  source = sys.argv[1]
  TYPES = ('.jpeg', '.png', '.jpg')
  
  def convert_a_img(img_file):
  	filename = os.path.split(img_file)[1]
  	url_out = os.path.join(source, '-'+filename)
  
  	subprocess.call(['guetzli', '--quality', '84', '--verbose', img_file, url_out])
  ###########################################################################
  #main
  
  def main():
  	if os.path.isdir(source):
  		for root, dirs, files in os.walk(source):
  			for a_file in files:
  				suffix = os.path.splitext(a_file)[1]
  				if suffix in TYPES:
  					convert_a_img(os.path.join(root, a_file))
  					pass
  
  	elif os.path.isfile(source):
  		convert_a_img(source)
  	
  	else:
  		print('Please check the input, not found any files or folders.')
  
  main()
  
new_contents: # -*- coding:utf-8 -*-
  import os
  import subprocess
  import sys
  
  source = sys.argv[1]
  TYPES = ('.jpeg', '.png', '.jpg')
  
  def convert_a_img(img_file):
  	filename = os.path.split(img_file)[1]
  	url_out = os.path.join(source, '-'+filename)
  
  	subprocess.call(['guetzli', '--quality', '84', '--verbose', img_file, url_out])
  ###########################################################################
  #main
  
  def main():
  	if os.path.isdir(source):
  		for root, dirs, files in os.walk(source):
  			for a_file in files:
  				suffix = os.path.splitext(a_file)[1]
  				if suffix in TYPES:
  					convert_a_img(os.path.join(root, a_file))
  					pass
  
  	elif os.path.isfile(source):
  		convert_a_img(source)
  	
  	else:
  		print('Please check the input, not found any files or folders.')
  
  main()
  
subject: Remove abandoned import