python 写一个贪吃蛇游戏

#!usr/bin/python
#-*- coding:utf-8 -*-

import random
import curses

s = curses.initscr()
curses.curs_set(0)
sh,sw = s.getmaxyx()
w = curses.newwin(sh,sw,0,0)
w.keypad(1)
w.timeout(100)

snk_x = sw/4
snk_y = sh/2
snake = [
        [snk_y,snk_x],
        [snk_y,snk_x-1],
        [snk_y,snk_x-2]
]

food = [sh/2,sw/2]
w.addch(food[0],food[1],curses.ACS_PI)

key = curses.KEY_RIGHT

while True:
    next_key = w.getch()
    key = key if next_key == -1 else next_key

    if snake[0][0] in [0,sh] or snake[0][1] in [0,sw] or snake[0] in snake[1:]:
        curses.endwin()
        quit()

    new_head = [snake[0][0], snake[0][1]]

    if key == curses.KEY_DOWN:
        new_head[0] +=1
    if key == curses.KEY_UP:
        new_head[0] -=1
    if key == curses.KEY_LEFT:
        new_head[1] -=1
    if key == curses.KEY_RIGHT:
        new_head[1] +=1

    snake.insert(0,new_head)

    if snake[0] == food:
        food = None
        while food is None:
            nf = [
                    random.randint(1,sh-1),
                    random.randint(1,sw-1)
                ]
            food = nf if nf not in snake else None
        w.addch(food[0],food[1],curses.ACS_PI)
    else:
        tail = snake.pop()
        w.addch(tail[0],tail[1],' ')

    w.addch(snake[0][0],snake[0][1],curses.ACS_CKBOARD)