docs: def _keyUp(key):
      """Performs a keyboard key release (without the press down beforehand).
  
      Args:
        key (str): The key to be released up. The valid names are listed in
        pyautogui.KEY_NAMES.
  
      Returns:
        None
      """
  
      """
      Release a given character key. Also works with character keycodes as
      integers, but not keysyms.
      """
      if key not in keyboardMapping or keyboardMapping[key] is None:
          return
  
      if type(key) == int:
          keycode = key
      else:
          keycode = keyboardMapping[key]
  
      fake_input(_display, X.KeyRelease, keycode)
      _display.sync()