Learning Python - cart program

Problem needs:

1, start the program that allows the user to enter wages, and then print the Product List

2, allows users to purchase by product number

3, after the user selects a product, testing the balance is enough, enough to direct debit, is not enough to remind

4, may at any time withdraw, exit, print the purchase of goods and balances

 1 __author__ = 'jcx'
 2 
 3 product_list = [
 4     ('iphone11',5000),
 5     ('macbook pro',9800),
 6     ('Bike',800),
 7     ('Coffee',31),
 8     ('jcx\'s C++',60),
 9 ]
10 
11 shoping_list = []
12 salary = input("Input your salary: ")
13 if salary.isdigit():
14     salary = int(salary)
15     while True:
16         for index,item in enumerate(product_list):
17             print(index,item)
18         user_choice = input("选择要买的商品>>>: ")
19         if user_choice.isdigit():
20             user_choice = int(user_choice)
21             if user_choice < len(product_list) and user_choice >= 0:
22                 p_item = product_list[user_choice]
23                 if p_item[1] <= salary: #买得起
24                     shoping_list.append(p_item)
25                     salary -= p_item[1]
26                     print("Added %s into shopping cart, your current balance is \033[31;1m%s\033[0m" % (p_item,salary))
27                 else:
28                     print("\033[41;1m你的余额只剩[%s]\033[0m" % salary)
29             else:
30                 print("product number [%s] is not exist." % user_choice)
31         elif user_choice == 'q':
32             print("------  shoping list -------")
33             for p in shoping_list:
34                 print(p)
35             print("You current balance: \033[31;1m%s\033[0m" % salary)
36             exit()
37         else:
38             print("invalid option")

 Output:

. 1 the Input your the salary: 6000
 2 0 ( ' iphone11 ' , 5000 )
 . 3 . 1 ( ' MacBook Pro ' , 9800 )
 . 4 2 ( ' Bike ' , 800 )
 . 5 . 3 ( ' Coffee ' , 31 is )
 . 6 . 4 ( " JCX apos C ++ " 60 )
 7 choose where to purchase >>> : 0
 . 8 Added ( ' iphone11 ' , 5000) INTO Shopping Cart,your current balance is 1000
. 9 0 ( ' iphone11 ' , 5000 )
 10 . 1 ( ' MacBook Pro ' , 9800 )
 . 11 2 ( ' Bike ' , 800 )
 12 is . 3 ( ' Coffee ' , 31 is )
 13 is . 4 ( " JCX apos C ++ " , 60 )
 14 to select SALE goods >>>:. 6
 15 product Number [. 6] iS  Not exist.
 16 0 ( ' iphone11 ' , 5000 )
 . 17 . 1 (' MacBook Pro ' , 9800 )
 18 is 2 ( ' Bike ' , 800 )
 . 19 . 3 ( ' Coffee ' , 31 is )
 20 is . 4 ( " JCX apos C ++ " , 60 )
 21 is selected item to buy >>> : Q
 22 is ---- - List Shoping -------
 23 is ( ' iphone11 ' , 5000 )
 24 by You Current Balance: 1000
 25  
26 is Process Finished Exit with code 0