Customize login in Google App Engine
You can't customize the login page. Allowing you to do so would introduce the possibility of XSS vulnerabilities, as well as making it harder for users to identify a legitimate login page.
If you want to provide for federated login, you may want to simply redirect users to an interstitial page that allows them to pick standard Google login, or one of a number of other services.
I need to add few more options for login and therefore need to customize create_login_url with some HTML code. 
Is there a way to add on your code in default login screen of Google?
Environment: Python (Google App Engine)
I want to continue having the default Google ext class Users behavior in place.