用户名密码对错的判断（if的用法）

_username="Ck"
_password="abc123"
username=input("username:")
password=input("password:")

if username==_username and password==_password:
    print("Welcome user {name} login...".format(name=username))
else:
    print("Invalid username or password!")

原文：https://www.cnblogs.com/shmilymima/p/9265488.html