import sys
import pygame
class AlienInvasion:
def __init__(self):
pygame.init()
self.screen=pygame.display.set_mode((100,800))
pygame.display.set_caption(“Alien Invasion”)
self.bg_color

def run_game(self):
while True:
for event in pygame.event.get():
if event.type==pygame.QUIT:
sys.exit()
self.screen.fill(self.bg_color)
pygame.display.flip()
if __name__=='__main__':
ai=AlienInvasion()
ai.run_game()