Problems with hotkey

[PeaceAndJoyAaron]

Hi,guys,I have currently written a test script with the following content
`import time
import pyautogui

time.sleep(1)

pyautogui.mouseDown(button='left')
pyautogui.mouseUp(button='left')
pyautogui.hotkey('ctrl', 'shift', 'down')
print('Script completed.')`

And I have also tried to write it in the following format

`import time
import pyautogui

time.sleep(1)

pyautogui.mouseDown(button='left')
pyautogui.mouseUp(button='left')
pyautogui.keyDown('ctrl')
pyautogui.keyDown('shift')
pyautogui.keyDown('down')
pyautogui.keyUp('down')
pyautogui.keyUp('shift')
pyautogui.keyUp('ctrl')
print('Script completed.')`

But currently, it seems that either way of writing will render 'shift' ineffective.
Looking forward to receiving a response, thank you very much