给一段贪吃蛇的python代码

好的，下面是一个简单的贪吃蛇游戏的Python代码示例，使用了pygame库来创建游戏界面：

import pygame
import random

# 初始化pygame
pygame.init()

# 设置窗口大小和标题
screen_width = 400
screen_height = 600
screen = pygame.display.set_mode((screen_width, screen_height))
pygame.display.set_caption("贪吃蛇")

snake_speed = 15
snake_color = (0, 255, 0)
food_color = (255, 0, 0)

# 初始化蛇的位置和大小
snake_pos = [(screen_width // 2, screen_height // 2)]
snake_size = 1
direction = "right"

# 定义食物生成位置
def generate_food():
    while True:
        food_x = random.randint(0, screen_width - snake_size)
        food_y = random.randint(0, screen_height - snake_size)
        if (food_x, food_y) not in snake_pos:
            return food_x, food_y

# 游戏主循环
while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            quit()
        elif event.type == pygame.KEYDOWN:
            if event.key == pygame.K_UP and direction != "down":
                direction = "up"
            elif event.key == pygame.K_DOWN and direction != "up":
                direction = "down"
            elif event.key == pygame.K_LEFT and direction != "right":
                direction = "left"
            elif event.key == pygame.K_RIGHT and direction != "left":
                direction = "right"

    # 更新蛇的位置
    new_head = list(snake_pos[-1])
    if direction == "up":
        new_head[1] -= snake_size
    elif direction == "down":
        new_head[1] += snake_size
    elif direction == "left":
        new_head[0] -= snake_size
    else:
        new_head[0] += snake_size
    snake_pos.append(new_head)

    # 检查边界和碰撞
    if new_head[0] < 0 or new_head[0] >= screen_width or new_head[1] < 0 or new_head[1] >= screen_height:
        print("Game Over! You hit the border.")
        break

    if new_head in snake_pos[:-1]:
        print("Game Over! You hit yourself.")
        break

    # 移除蛇尾
    snake_pos.pop(0)

    # 画蛇和食物
    screen.fill((0, 0, 0))
    for pos in snake_pos:
        pygame.draw.rect(screen, snake_color, [pos[0], pos[1], snake_size, snake_size])
    food_x, food_y = generate_food()
    pygame.draw.rect(screen, food_color, [food_x, food_y, snake_size, snake_size])

    # 更新屏幕
    pygame.display.update()
    pygame.time.delay(snake_speed)

# 结束游戏
pygame.quit()