基础的购物车程序

# Author：Zhang
product_list =[
    ('Iphone',5800),
    ('Mac Pro', 9800),
    ('Bike', 800),
    ('Watch', 10600),
    ('Coffee', 31),
    ('Zhang Python', 120)
]
shopping_list =[]
salary = input("Input your salary:")
if salary.isdigit():    #判断是否是数字
    salary =int(salary)
    while True:                                        # index,item    带下标的列表
        for index,item in enumerate(product_list):     #for item in product_list:     列表显示下标
            print(index,item)                           #    print(product_list.index(item),item)
        user_choice =input("选择你要购买的商品编号>>>:")
        if user_choice.isdigit():
            user_choice =int(user_choice)
            if user_choice <len(product_list) and user_choice>=0:
                p_item =product_list[user_choice]
                if p_item[1]<= salary:  #买得起
                    shopping_list.append(p_item)
                    salary -= p_item[1]                                             #\033[31;1m%s\033[0m  高亮显示
                    print("Added %s into shopping cart,your current balance is \033[31;1m%s\033[0m"%(p_item,salary))
                else:
                    print("\033[41;1m你的余额只剩[%s]啦，请留意！！！\033[0m"% salary)
            else:
                print("product code [%s] is not exist!"%user_choice)
        elif user_choice=='q':
            print("-----------Shopping List-------------")
            for p in shopping_list:
                print(p)
            print("Your current balance:",salary)
            exit()
        else:
            print("invalid option")