diy2.py

username = "python"
userpassword = "123456"
i=3
while True:
    if i > 0:
        name = input("请输入用户名:")
        password = input("请输入密码:")
        i = i - 1 
        if name == username and password == userpassword:
            print("登录成功!")
            break
        if username != name:
            print("输入用户名错误")
            print("您还有"+str(i)+"次机会")
            continue
        if password != userpassword:
            print("输入密码错误")
            print("您还有"+str(i)+"次机会")
    else:
        print("您的账号被锁定")
        exit()              
print("欢迎来到贝尔编程!")