add() argument after * must be an iterable, not Setting pygame编写小游戏时报错

Question

用pygame编写程序时报错，小白求大佬们指点，在线等！！
def check_keydown_events(event,ai_settings,screen,ship,bullets):
"""响应按键"""
if event.key == pygame.K_RIGHT:
ship.moving_right = True
if event.key == pygame.K_LEFT:
ship.moving_left = True
elif event.key == pygame.K_SPACE:
new_bullet = Bullet(ai_settings,screen,ship)
bullets.add(new_bullet)

            File "E:\python\aline_invasion\game_functions.py", line 26, in check_events
check_keydown_events(event,ai_settings,screen,ship,bullets)

File "E:\python\aline_invasion\game_functions.py", line 11, in check_keydown_events
new_bullet = Bullet(ai_settings,screen,ship)
File "E:\python\venv\lib\site-packages\pygame\sprite.py", line 124, in init
self.add(*groups)
File "E:\python\venv\lib\site-packages\pygame\sprite.py", line 142, in add
self.add(*group)
TypeError: add() argument after * must be an iterable, not Setting

Answer 1

是不是《python从入门到实践》这本书上的Alien invasion小游戏？我也是编写这个游戏的时候遇到错误了，蹲个大佬解答