old_contents: def yesno(prompt='? '):
  	# raw_input returns the empty string for "enter"
  	yes = set(['yes','y', 'ye', ''])
  	no = set(['no','n'])
  
  	choice = input(prompt).lower()
  	if choice in yes:
  		return True
  	elif choice in no:
  		return False
  	else:
  		sys.stdout.write("Please respond with 'yes' or 'no'")
  
new_contents: from six.moves import input
  
  def yesno(prompt='? '):
  	# raw_input returns the empty string for "enter"
  	yes = set(['yes','y', 'ye', ''])
  	no = set(['no','n'])
  
  	choice = input(prompt).lower()
  	if choice in yes:
  		return True
  	elif choice in no:
  		return False
  	else:
  		sys.stdout.write("Please respond with 'yes' or 'no'")
  
subject: Support input() on python 2.