python小练习:用户三次登陆, 购物车

from random import randint
i = 1
while i < 4:
    num = 0
    verify_code = ''
    while num < 4:
        verify_code = verify_code + chr(randint(65, 90)) #将随机生成的4个字符连接起来
        num += 1
    print(verify_code)
    username = input('请输入用户名:').strip()
    password = input('请输入密码:').strip()
    v_code = input('请输入验证码').upper()
    if username == 'alex' and password == '123':
        if v_code == verify_code:
            print('登陆成功')
            break
        else:
            print('验证码输入错误,请重新输入')
    else:
        # print('账号或密码输入有误!,还有%s次机会请重新输入' % (3-i))
        if username == 'alex' and password != '123':
            print('密码错误,还有%s次机会请重新输入' % (3-i))
        else:
            print('没有此账号,还有%s次机会请重新输入' % (3-i))
    i += 1

goods = [{"name": "电脑", "price": 1999},
         {"name": "鼠标", "price": 10},
         {"name": "游艇", "price": 20},
         {"name": "飞机", "price": 998}, ]

while 1:
    username = input('请输入用户名:').strip()
    password = input('请输入密码:').strip()
    shopping = {}if username == 'alex' and password == '123':
        money = int(input('请输入工资'))
        yu_e = 0
        i = 0
        while 1:
            while i < len(goods):
                print('''
                商品编号    商品名    价格
                   %s        %s        %s''' % ((i + 1), goods[i]['name'], goods[i]['price']))
                i += 1
            buy_bianhao = input('请输入要购买的商品编号(按q退出):').strip()
            if buy_bianhao.upper() == 'Q':
                if len(shopping) > 0:
                    print('购买的商品:')
                    for k, v in shopping.items():#遍历shopping中的key和value
                        print('商品:%s, 价格:%s' % (k, v))
                    print('余额为:%s' % money)
                    break
                else:
                    print('没有买东西')
                    break
            else:
                index = int(buy_bianhao) - 1
                if money - goods[index]['price'] >= 0:
                    print('成功购买')
                    money -= goods[index]['price']   #剩余工资
                    shopping[goods[index]['name']] = goods[index]['price']  #将购买的商品作为key,price作为value,存入字典shopping中
                    # print('剩余%s:' % money)
                    # print(shopping)#
                else:
                    print("您的余额不足.")
        if buy_bianhao.upper() == 'Q':  #判断是否退出
            break

    else:
        print('账号或密码不正确,请重新输入')