本人不善言辞，不废话，直接上代码：

#!/usr/bin/env python# -*- coding: utf-8 -*-#_auth by kkdef goods_list():    shangpin={"iphone":"6000","MacAir":"15000","tea":"50","book":"30"}    print "-"*12 +u"商品列表" +"-"*12    for key in shangpin:        print "goods: %s --> price: %s" % (key,shangpin[key])    print "-"*12 +u"商品列表" +"-"*12    return shangpindef jiesuan(money,shangpin_list):    sheng_money=money    while True:        qt=raw_input(u"您需要购物吗？y/n \n")        if qt=="y":            gou_goods=raw_input(u"请输入您想购买的商品名字，购买的商品请参考商品列表：\n")            if gou_goods in shangpin_list:                sheng_money=int(sheng_money)-int(shangpin_list[gou_goods])                if sheng_money>=0:                    print " 您购买了%s商品，共消费 %s, 您还剩 %s元钱！" % (gou_goods,shangpin_list[gou_goods],sheng_money)                else:                    print "您的金钱不足,请充值，欢迎下次光临！"                    break            else:                print "没有此商品！"        else:            print "欢迎下次光临！"            breakif __name__== '__main__':    shangpin_list=goods_list()    try:        money=raw_input(u"请充值后在购买商品，请输入充值金额：\n")        print "您的充值金额为 %s,充值成功！"% (money)    except IOError,e:        print "输入错误，请检查!"    jiesuan(money,shangpin_list)