用python给我写一个贪吃蛇游戏

好的，以下是一个简单的贪吃蛇游戏的Python代码：

import pygame
import random

# 定义颜色
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
GREEN = (0, 255, 0)
RED = (255, 0, 0)

# 设置屏幕大小
SCREEN_WIDTH = 600
SCREEN_HEIGHT = 600

# 定义蛇的初始位置和大小
SNAKE_SIZE = 10
SNAKE_X = SCREEN_WIDTH / 2
SNAKE_Y = SCREEN_HEIGHT / 2
SNAKE_SPEED = 10

# 初始化pygame
pygame.init()

# 设置屏幕大小
screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))
pygame.display.set_caption("贪吃蛇")

# 定义蛇的初始方向
direction = "right"

# 定义食物的位置
food_x = round(random.randrange(0, SCREEN_WIDTH - SNAKE_SIZE) / 10.0) * 10.0
food_y = round(random.randrange(0, SCREEN_HEIGHT - SNAKE_SIZE) / 10.0) * 10.0

# 初始化得分和蛇的长度
score = 0
snake_length = 1
snake_list = []

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

        # 获取键盘输入，改变蛇的方向
        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT:
                direction = "left"
            elif event.key == pygame.K_RIGHT:
                direction = "right"
            elif event.key == pygame.K_UP:
                direction = "up"
            elif event.key == pygame.K_DOWN:
                direction = "down"

    # 根据方向移动蛇的位置
    if direction == "right":
        SNAKE_X += SNAKE_SPEED
    elif direction == "left":
        SNAKE_X -= SNAKE_SPEED
    elif direction == "up":
        SNAKE_Y -= SNAKE_SPEED
    elif direction == "down":
        SNAKE_Y += SNAKE_SPEED

    # 绘制背景
    screen.fill(BLACK)

    # 绘制食物
    pygame.draw.rect(screen, GREEN, [food_x, food_y, SNAKE_SIZE, SNAKE_SIZE])

    # 绘制蛇
    snake_head = []
    snake_head.append(SNAKE_X)
    snake_head.append(SNAKE_Y)
    snake_list.append(snake_head)

    if len(snake_list) > snake_length:
        del snake_list[0]

    for segment in snake_list[:-1]:
        if segment == snake_head:
            game_over = True

    for segment in snake_list:
        pygame.draw.rect(screen, WHITE, [segment[0], segment[1], SNAKE_SIZE, SNAKE_SIZE])

    # 检查蛇是否吃到食物
    if SNAKE_X == food_x and SNAKE_Y == food_y:
        food_x = round(random.randrange(0, SCREEN_WIDTH - SNAKE_SIZE) / 10.0) * 10.0
        food_y = round(random.randrange(0, SCREEN_HEIGHT - SNAKE_SIZE) / 10.0) * 10.0
        score += 10
        snake_length += 1

    # 显示得分
    font = pygame.font.SysFont('arial', 20)
    text = font.render("得分: " + str(score), True, WHITE)
    screen.blit(text, [0, 0])

    # 刷新屏幕
    pygame.display.update()

    # 控制游戏速度
    clock = pygame.time.Clock()
    clock.tick(20)

# 退出游戏
pygame.quit()

这个游戏可能不是非常完美，但是可以作为一个简单的贪吃蛇游戏的例子。