vcj.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:
        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("密码输入有误,请重新输入！")
print("欢迎来到贝尔编程")