code: def one(prompt, *args, **kwargs):
      
      indicator = '‣'
      if sys.version_info < (3, 0):
          indicator = '>'
  
      def go_back(picker):
          return None, -1
  
      options, verbose_options = prepare_options(args)
      idx = kwargs.get('idx', 0)
  
      picker = Picker(verbose_options, title=prompt, indicator=indicator, default_index=idx)
      picker.register_custom_handler(ord('h'), go_back)
      picker.register_custom_handler(curses.KEY_LEFT, go_back)
      with stdout_redirected(sys.stderr):
          option, index = picker.start()
          if index == -1:
              raise QuestionnaireGoBack
          if kwargs.get('return_index', False):
              # `one` was called by a special client, e.g. `many`
              return index
          return options[index]
docs: Instantiates a picker, registers custom handlers for going back,
      and starts the picker.