diy2.py

username = "python"
userpassword = "123456"
while True:
    name = input("请输入用户名:")
    password = input("请输入密码:")
    if name == username and password == userpassword:
         if name("输入密码错误，请重新打开")
         name!username
         if password("输入账号错误，请重新打开")
         password!userpassword
         print("你的账号不存在，请等等打开")
        print("登录成功!")
    print("用户名和密码错误!请重新输入")
    print("密码输入过多，请带身份证")
print("欢迎来到贝尔编程!")