# -*- conding:utf-8 -*-

# 登錄驗證
def login(password):
    pwd = ‘888888‘ # 默認密碼
    if password == pwd:
        return  True
    else:
        return False
# 金額驗證
def checkMoney(money):
    if money.isdigit():
        if int(money) % 100 == 0 and 0<= int(money)<=1000:
            return money
        
 
else:
            return  False
    else:
        return  False

#業務邏輯寫到主程序
def main( ):
    #1.登錄驗證
    for i in range(3):
        password = input("輸入密碼： ")
        if login(password):
        # 2.金額驗證
            while True:
                money = input("請輸入金額：")
                money = checkMoney(money)
                
 
if money:
                    print("成功取出%s元"%(money))
                    break
                else:
                    print("您輸入的金額有誤，請重新輸入")
             # 3.交易完成
            print("交易完成,請取卡")
        else:
            if i == 2:
                print("您已連續輸入3次密碼有誤，賬號已凍結")
                break
 

            print("密碼錯誤")
main()

簡單的ATM機的取款過程