python 购物车

要求实现功能：
启动程序后，用户输入工资，然后打印商品列表
允许用户根据商品编号购买商品
用户选择商品后，检测余额是否够，够就直接扣款，不够就提醒
可随时退出，退出时， 打印已购买商品和余额

product_list = [ ('iphone', 8100),
                 ('mac pro', 13000),
                 ('sea food', 600),
                 ('bed', 3200),
                 ('chair', 123),
                 ('blue tooth header', 1800)


]

shopping_list = []
salary = input("please input your salary here: ")
if salary.isdigit():                    #判断工资是不是数字
    salary = int(salary)                #工资是数字，把salary类型变成int
    while True:                         #进入循环
        for index, item in enumerate(product_list):
             print(index, product_list)

        user_choice = input("please put number to choice what you want>>>>>>:")
        if user_choice.isdigit():          #判断用户输入必须是数字
           user_choice = int(user_choice)
           if user_choice < len(product_list) and user_choice >= 0:    #用户选择的数字小于product list长度 且大于等于0
               p_item = product_list[user_choice]

               if p_item[1] <= salary:
                   shopping_list.append(p_item)  #shopping list 里增加该item
                   salary -= p_item[1]         #购买物品后在工资里扣除相应的钱
                   print("you have added %s into your shopping cart, and your current balance is: 33[31;1m%s33[0m" %(p_item,salary))
    # 33[31;1m%s33[0m   字体颜色改成红色
               else:
                   print("33[31;1m you don't have enough salary!33[0m")
           else:
               print("%s is no exist option!" %user_choice)


        elif user_choice == 'q':
            print("----------------your shopping list---------------")
            for p in shopping_list:
                print(p)
            print(" your current balance is:", salary)
            exit()
        else:
            print("invalid option")

使用 for index, item in enumerate(product_list)使 product_list更加灵活，后期可增加删除里面元素并且不影响原有代码
注： 在list打印出来的时候是这样的：（尚未解决）

0 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]
1 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]
2 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]
3 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]
4 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]
5 [('iphone', 8100), ('mac pro', 13000), ('sea food', 600), ('bed', 3200), ('chair', 123), ('blue tooth header', 1800)]

但是不影响购买