用户登陆认证

# ！/usr/bin/env python
# -*- conding: utf-8 -*-
# Author:jack chen  2018/04/29

_username = 'alex'
_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 and password!")