python写一个简单的贪吃蛇

好的，下面是一个简单的贪吃蛇游戏的 Python 代码：

import pygame
import random

# 游戏初始化
pygame.init()

# 游戏窗口大小
win_width = 500
win_height = 500
win = pygame.display.set_mode((win_width, win_height))
pygame.display.set_caption("贪吃蛇")

# 颜色定义
black = (0, 0, 0)
white = (255, 255, 255)
green = (0, 255, 0)
red = (255, 0, 0)

# 蛇的初始位置和大小
snake_block = 10
snake_list = []
snake_length = 1

# 蛇的移动速度
speed = 15

# 随机食物的位置
food_x = round(random.randrange(0, win_width - snake_block) / 10.0) * 10.0
food_y = round(random.randrange(0, win_height - snake_block) / 10.0) * 10.0

# 游戏结束的标志
game_over = False

# 设置字体
font_style = pygame.font.SysFont(None, 50)


# 显示分数
def show_score(score):
    score_font = font_style.render("得分: " + str(score), True, white)
    win.blit(score_font, [0, 0])


# 画蛇
def draw_snake(snake_block, snake_list):
    for x in snake_list:
        pygame.draw.rect(win, green, [x[0], x[1], snake_block, snake_block])


# 显示消息
def message(msg, color):
    msg_font = font_style.render(msg, True, color)
    win.blit(msg_font, [win_width / 6, win_height / 3])


# 游戏循环
while not game_over:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            game_over = True

        # 蛇的移动
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                x_change = -snake_block
                y_change = 0
            elif event.key == pygame.K_RIGHT:
                x_change = snake_block
                y_change = 0
            elif event.key == pygame.K_UP:
                x_change = 0
                y_change = -snake_block
            elif event.key == pygame.K_DOWN:
                x_change = 0
                y_change = snake_block

    # 蛇头的位置
    snake_head = []
    snake_head.append(food_x)
    snake_head.append(food_y)
    snake_list.append(snake_head)

    # 当蛇的长度超过设定值时，删除蛇尾
    if len(snake_list) > snake_length:
        del snake_list[0]

    # 当蛇头和食物重合时，重新生成食物，并且蛇的长度加1
    if food_x == snake_head[0] and food_y == snake_head[1]:
        food_x = round(random.randrange(0, win_width - snake_block) / 10.0) * 10.0
        food_y = round(random.randrange(0, win_height - snake_block) / 10.0) * 10.0
        snake_length += 1

    # 当蛇头碰撞到墙壁或者碰到自己的身体时，游戏结束
    if snake_head[0] >= win_width or snake_head[0] < 0 or snake_head[1] >= win_height or snake_head[1] < 0:
        game_over = True
    for x in snake_list[:-1]:
        if x == snake_head:
            game_over = True

    # 游戏窗口背景颜色
    win.fill(black)

    # 画食物和蛇
    pygame.draw.rect(win, red, [food_x, food_y, snake_block, snake_block])
    draw_snake(snake_block, snake_list)

    # 显示分数
    show_score(snake_length - 1)

    # 更新游戏窗口
    pygame.display.update()

    # 蛇的移动
    food_x += x_change
    food_y += y_change

    # 控制游戏速度
    clock = pygame.time.Clock()
    clock.tick(speed)

# 游戏结束时显示分数
message("游戏结束", red)
pygame.display.update()

# 游戏结束后等待3秒钟，然后退出游戏
pygame.time.wait(3000)

# 退出游戏
pygame.quit()
quit()

注意：本代码仅为一个简单的贪吃蛇游戏，还有很多需要改进的地方，比如蛇的移动方式、游戏难度等。