docs: def _keyDown(key):
      """Performs a keyboard key press without the release. This will put that
      key in a held down state.
  
      NOTE: For some reason, this does not seem to cause key repeats like would
      happen if a keyboard key was held down on a text field.
  
      Args:
        key (str): The key to be pressed down. The valid names are listed in
        pyautogui.KEY_NAMES.
  
      Returns:
        None
      """
      if key not in keyboardMapping or keyboardMapping[key] is None:
          return
  
      needsShift = pyautogui.isShiftCharacter(key)
  
      """
      # OLD CODE: The new code relies on having all keys be loaded in keyboardMapping from the start.
      if key in keyboardMapping.keys():
          vkCode = keyboardMapping[key]
      elif len(key) == 1:
          # note: I could use this case to update keyboardMapping to cache the VkKeyScan results, but I've decided not to just to make any possible bugs easier to reproduce.
          vkCode = ctypes.windll.user32.VkKeyScanW(ctypes.wintypes.WCHAR(key))
          if vkCode == -1:
              raise ValueError('There is no VK code for key "%s"' % (key))
          if vkCode > 0x100: # the vk code will be > 0x100 if it needs shift
              vkCode -= 0x100
              needsShift = True
      """
      mods, vkCode = divmod(keyboardMapping[key], 0x100)
  
      for apply_mod, vk_mod in [(mods & 4, 0x12), (mods & 2, 0x11),
          (mods & 1 or needsShift, 0x10)]: #HANKAKU not suported! mods & 8
          if apply_mod:
              ctypes.windll.user32.keybd_event(vk_mod, 0, 0, 0) #
      ctypes.windll.user32.keybd_event(vkCode, 0, 0, 0)
      for apply_mod, vk_mod in [(mods & 1 or needsShift, 0x10), (mods & 2, 0x11),
          (mods & 4, 0x12)]: #HANKAKU not suported! mods & 8
          if apply_mod:
              ctypes.windll.user32.keybd_event(vk_mod, 0, KEYEVENTF_KEYUP, 0)