i = 3
username = "python"
userpassword = "123456"
while True:
    if i>0:
        name = input("请输入用户名:")
        password = input("请输入密码:")
        i -= 1
        if name == username and password == userpassword:
            print("登录成功!")
            break
        if name != username:
            print("用户名错误，请重新输入！")
            continue
        if password != userpassword:
            print("密码输入错误，请重新输入！")
    else:
        print("你的账号已被锁定，请一个小时后再来")
        exit()
print("欢迎来到贝尔编程!")