code: def wait_for_keys(self, *keys, timeout=0):
          
          if len(keys) == 1 and _is_iterable(keys[0]):
              keys = keys[0]
  
          return self.listen_until_return(Handler.key_press(keys), timeout=timeout)
docs: Waits until one of the specified keys was pressed, and returns 
          which key was pressed.
  
          :param keys: iterable of integers of pygame-keycodes, or simply 
              multiple keys passed via multiple arguments
          :type keys: iterable
          :param timeout: number of seconds to wait till the function returns
          :type timeout: float
  
          :returns: The keycode of the pressed key, or None in case of timeout
          :rtype: int