加入time模塊，在退出系統前等待2s

 1 import time
 2 product_list = [
 3     (‘iphone‘,5800),
 4     (‘Mac Pro‘, 10800),
 5     (‘Bike‘, 800),
 6     (‘Coffee‘, 31),
 7     (‘iWatch‘, 6800),
 8     (‘ArcherZon Python‘, 102),
 9 ]
10 salary = input("Enter your salary:")
11 shopping_list = []
12 exit_flag = False
13 while not
 
 exit_flag:
14     if salary.isdigit():
15         salary = int(salary)
16         while not exit_flag:
17             for index,item in enumerate(product_list):
18                 print(index,item)
19             user_choice = input("選擇你要購買的商品：")
20             if user_choice.isdigit():
21                 user_choice = int(user_choice)
 
22                 if user_choice < len(product_list) and user_choice >= 0:
23                     p_item = product_list[user_choice]
24                     if p_item[1] < salary:
25                         shopping_list.append(p_item)
26                         salary -= p_item[1]
27                         print
 
("You have bought \031[31m;1m%s\033[0m.Your current balance is \033[31;1m%s\033[0m."%(p_item[0],salary))
28                     else:
29                         print("余額不足，僅剩\033[31;1m%s\033[0m."%salary)
30                 elif user_choice == ‘q‘:
31                     print("即將打印購物清單，請稍等...")
32                     time.sleep()
33                     print("-----shopping_list-----")
34                     for p in shopping_list:
35                         print(p)
36                     print("Your current balance is \033[31;1m%s\033[0m."%salary)
37                     exit_flag = True
38                 else:
39                     print("\033[31;1minvalid option!\033[0m")
40             else:
41                 print("\033[31;1minvalid option!\033[0m")
42     elif salary == ‘q‘:
43         print("即將退出，請稍等...")
44         time.sleep(2)
45         exit_flag = True
46     else:
47         print("\033[31;1minvalid option!\033[0m")

購物車小優化