问Python列表/字典不保留用户输入

EN

#PART 1

Customers=[]
Customer_name=input("Please enter your name: ") #User name Input
Customers.append(Customer_name)
Mem_Customers=[]
items={"Shirt":100, "Trouser":150, "Shorts":50, "Tshirt":100}  
Products=["Shirt","Trouser","Shorts","Tshirt"] 
Price=[100,150,50,100]

def menu():
print(" Welcome to RMIT Retail Management System")
print()
print("#"*40)
print()
print("Please choose form the following options")
print("1: Place an order")
print("2: Add/Update Products and Prices")
print("3: Display existing Customers")
print("4: Display existing Customers with Membership")  
print("5: Display existing Products")  
print("0: Exit the menu" ) 
print()  
print("#"*40)
menu()
option=input(" Choose one Option:")

while int(option)!=0:
if int(option)==1:
Choose_Product=input("Please enter the product you want to choose (valid product only i.e Shirt,Trouser,Shorts,Tshirt) : ")

        while not Choose_Product in items:
            print("Please enter a valid product")
            Choose_Product=input("Please enter the product you want to choose (valid product only i.e Shirt,Trouser,Shorts,Tshirt) : ")
        
        
        valid_quantity= False
        while not valid_quantity:
            Quantity=input("Please enter the quantity of the products required(Positive integer only): ") 
            if Quantity.strip().isdigit() and int(Quantity)>0:
                valid_quantity= True
            else:
                print("Please enter a valid integer")
    
        
        
        response=False
        while not response:  
            Membership=input("Please specify that you want a membership or not Y/N : ") 
            if Membership  in "Y" "N":
                response=True
            else:
                print("Please enter a valid response")
    
        
    
    
    
    # Membership
        if Membership=="Y" and Choose_Product=="Shirt":
            Mem_Customers.append(Customer_name)
            print(Customer_name  +"purchases"+str(Quantity)+ "x"+ Choose_Product)
            print("Unit price :      100 AUD")
            print(Customer_name+"Gets a discount of 5%")
            totalprice=(items["Shirt"]*int(Quantity))
            finalprice=totalprice-(totalprice*0.05)
            print("Total price : "+str(finalprice))
    
        if Membership=="Y" and Choose_Product=="Trouser":
            Mem_Customers.append(Customer_name)
            print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
            print("Unit price :      150 AUD")
            print(Customer_name+"Gets a discount of 5%")
            totalprice=(items["Trouser"]*int(Quantity))
            finalprice=totalprice-(totalprice*0.05)
            print("Total price : "+str(finalprice))
    
        if Membership=="Y" and Choose_Product=="Shorts":
                Mem_Customers.append(Customer_name)
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      50 AUD")
                print(Customer_name+"Gets a discount of 5%")
                totalprice=(items["Shorts"]*int(Quantity))
                finalprice=totalprice-(totalprice*0.05)
                print("Total price : "+str(finalprice))
    
        if Membership=="Y" and Choose_Product=="Tshirt":
                Mem_Customers.append(Customer_name)
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      100 AUD")
                print(Customer_name+"Gets a discount of 5%")
                totalprice=(items["Tshirt"]*int(Quantity))
                finalprice=totalprice-(totalprice*0.05)
                print("Total price : "+str(finalprice))
    
        # No Membership
    
        if Membership=="N" and Choose_Product=="Shirt":             
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      100 AUD")
                totalprice=(items["Shirt"]*int(Quantity))
                finalprice=totalprice
                print("Total price : "+str(finalprice))
    
        if Membership=="N" and Choose_Product=="Trouser":
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      150 AUD")
                totalprice=(items["Trouser"]*int(Quantity))
                finalprice=totalprice
                print("Total price : "+str(finalprice))
    
        if Membership=="N" and Choose_Product=="Shorts":
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      50 AUD")
        
                totalprice=(items["Shorts"]*int(Quantity))
                finalprice=totalprice
                print("Total price : "+str(finalprice))
    
        if Membership=="N" and Choose_Product=="Tshirt":
                print(Customer_name +"purchases"+str(Quantity)+ "x"+ Choose_Product)
                print("Unit price :      100 AUD")
                totalprice=(items["Tshirt"]*int(Quantity))
                finalprice=totalprice
                print("Total price : "+str(finalprice))  
               
    
    
    
    if int(option)==2: 
        add_product=input("Please enter the new products separated by , :").split(",")
        Products.append(add_product)
        add_price=input("Please enter the price of the products separated by , :").split(",")
        Price.append(add_price)
        for i in range(len(add_product)):
            add_product[i]=add_product[i]
            add_price[i]=add_price[i]
    
            if add_product[i] in items:
                print("The product already exists and prices will be updated")
                items[add_product[i]]=add_price[i]
            else:
                print("New product has been entered and will be updated ")
                items[add_product[i]]=add_price[i]
            
    if int(option)==3:
        print()
        print("The existing customers are:""\n")
        print(list(set(Customers)))
        break
    if int(option)==4:
        print()
        print("The customers with membership are:""\n")
        print(list(set(Mem_Customers)))
        break
    if int(option)==5:
        print()
        print("The existing products are:""\n")
        print(list(set(Products)))
        break

if int(option)==0:
print()
print("Thanks for using our program bye..""\n")

menu()