做一个基于python的飞机大战代码，不需要添加其他东西

好的，下面是一个简单的飞机大战代码，仅供参考：

import pygame
import random

# 初始化 pygame
pygame.init()

# 设置窗口大小
screen_width = 480
screen_height = 700
screen = pygame.display.set_mode((screen_width, screen_height))

# 设置窗口标题
pygame.display.set_caption("飞机大战")

# 加载背景图片
background = pygame.image.load("images/background.png")

# 加载飞机图片
player_plane = pygame.image.load("images/player.png")

# 加载子弹图片
bullet = pygame.image.load("images/bullet.png")

# 加载敌机图片
enemy_plane = pygame.image.load("images/enemy.png")

# 设置字体
font = pygame.font.SysFont(None, 36)

# 设置游戏状态
game_over = False

# 设置计分
score = 0

# 定义函数：绘制飞机
def draw_plane(x, y):
    screen.blit(player_plane, (x, y))

# 定义函数：绘制子弹
def draw_bullet(x, y):
    screen.blit(bullet, (x, y))

# 定义函数：绘制敌机
def draw_enemy(x, y):
    screen.blit(enemy_plane, (x, y))

# 定义函数：显示分数
def show_score(score):
    score_text = font.render("分数：" + str(score), True, (255, 255, 255))
    screen.blit(score_text, (10, 10))

# 初始化飞机位置
player_x = screen_width // 2 - 50
player_y = screen_height - 150

# 初始化子弹位置
bullet_x = player_x + 36
bullet_y = player_y - 20
bullet_speed = 10
bullet_state = "ready"

# 初始化敌机位置
enemy_x = random.randint(0, screen_width - 64)
enemy_y = -64
enemy_speed = 5

# 设置游戏循环
while not game_over:
    # 处理事件
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            game_over = True
        elif event.type == pygame.KEYDOWN:
            if event.key == pygame.K_SPACE and bullet_state == "ready":
                bullet_x = player_x + 36
                bullet_y = player_y - 20
                bullet_state = "fire"
            elif event.key == pygame.K_LEFT:
                player_x -= 10
            elif event.key == pygame.K_RIGHT:
                player_x += 10

    # 绘制背景
    screen.blit(background, (0, 0))

    # 绘制飞机
    draw_plane(player_x, player_y)

    # 绘制子弹
    if bullet_state == "fire":
        draw_bullet(bullet_x, bullet_y)
        bullet_y -= bullet_speed
        if bullet_y < 0:
            bullet_state = "ready"

    # 绘制敌机
    draw_enemy(enemy_x, enemy_y)
    enemy_y += enemy_speed
    if enemy_y > screen_height:
        enemy_x = random.randint(0, screen_width - 64)
        enemy_y = -64

    # 碰撞检测
    if bullet_state == "fire" and enemy_x < bullet_x < enemy_x + 64 and enemy_y < bullet_y < enemy_y + 64:
        score += 10
        bullet_state = "ready"
        enemy_x = random.randint(0, screen_width - 64)
        enemy_y = -64

    if enemy_x < player_x < enemy_x + 64 and enemy_y < player_y < enemy_y + 64:
        game_over = True

    # 显示分数
    show_score(score)

    # 更新屏幕
    pygame.display.update()

# 退出游戏
pygame.quit()