帮我生成一个python的飞机大战游戏

好的，这里提供一个简单的飞机大战游戏的Python代码，你可以在此基础上进行修改和完善：

import pygame
import random
 
# 初始化
pygame.init()       
 
# 设置游戏窗口大小
screen = pygame.display.set_mode((480, 800))    
 
# 设置游戏标题
pygame.display.set_caption("飞机大战")    
 
# 加载图片
bg = pygame.image.load("images/background.png")    
hero = pygame.image.load("images/hero.png")      
enemy1 = pygame.image.load("images/enemy1.png")
enemy2 = pygame.image.load("images/enemy2.png")
enemy3 = pygame.image.load("images/enemy3.png")
bullet = pygame.image.load("images/bullet.png")
 
# 设置字体
font = pygame.font.Font(None, 36)
 
# 设置游戏变量
score = 0
hero_x = 200
hero_y = 600
hero_speed = 5
enemy_list = []
bullet_list = []
 
# 设置敌机类
class Enemy():
    def __init__(self, img, speed):
        self.img = img
        self.speed = speed
        self.width = self.img.get_rect().width
        self.height = self.img.get_rect().height
        self.x = random.randint(0, 480 - self.width)
        self.y = -self.height
 
    def move(self):
        self.y += self.speed
 
    def draw(self):
        screen.blit(self.img, (self.x, self.y))
 
# 设置子弹类
class Bullet():
    def __init__(self, img, speed):
        self.img = img
        self.speed = speed
        self.width = self.img.get_rect().width
        self.height = self.img.get_rect().height
        self.x = hero_x + hero.get_rect().width / 2 - self.width / 2
        self.y = hero_y - self.height
 
    def move(self):
        self.y -= self.speed
 
    def draw(self):
        screen.blit(self.img, (self.x, self.y))
 
# 设置主循环
while True:
    # 绘制背景
    screen.blit(bg, (0, 0))
 
    # 绘制分数
    text = font.render("Score: %d" % score, True, (255, 255, 255))
    screen.blit(text, (0, 0))
 
    # 绘制英雄
    screen.blit(hero, (hero_x, hero_y))
 
    # 绘制敌机
    for enemy in enemy_list:
        enemy.move()
        enemy.draw()
        if enemy.y > 800:
            enemy_list.remove(enemy)
            score += 1
 
    # 绘制子弹
    for bullet in bullet_list:
        bullet.move()
        bullet.draw()
        if bullet.y < 0:
            bullet_list.remove(bullet)
 
    # 控制英雄移动
    keys = pygame.key.get_pressed()
    if keys[pygame.K_LEFT] and hero_x > 0:
        hero_x -= hero_speed
    if keys[pygame.K_RIGHT] and hero_x < 480 - hero.get_rect().width:
        hero_x += hero_speed
 
    # 控制子弹发射
    if keys[pygame.K_SPACE]:
        bullet_list.append(Bullet(bullet, 10))
 
    # 控制敌机生成
    if random.randint(0, 100) < 3:
        enemy_type = random.randint(1, 3)
        if enemy_type == 1:
            enemy_list.append(Enemy(enemy1, random.randint(1, 3)))
        elif enemy_type == 2:
            enemy_list.append(Enemy(enemy2, random.randint(1, 3)))
        elif enemy_type == 3:
            enemy_list.append(Enemy(enemy3, random.randint(1, 3)))
 
    # 事件处理
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            exit()
 
    # 刷新屏幕
    pygame.display.update()

你可以将这段代码保存为一个Python文件，然后将所需的图片放在`images`文件夹下运行。注意：本代码并不包含游戏结束和游戏暂停等功能，需要自己添加。