diy2.py

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 username!=name:
            print("用户名错误!请重新输入")
            continue
        if userpassword!=password:
            print("密码错误!请重新输入")
    else:
        print("账号已被封禁,请到我司解锁")
        exit()
        print("用户名和密码错误!请重新输入")
print("欢迎来到贝尔编程!")