验证用户名及密码登陆
import getpass #导入getpass
_username='mei' #存储用户名为mei
_password='147' #存储密码为147
username=input('username:')
password=getpass.getpass('password:')
if _username==username and _password==password:
print('Congratulations!Welcome {name} login...'.format(name=username))
else:
print('Invalid username or password!')