Hello,
First of all, I want to ask you why you've chosen web2py for your project.
In my opinion, web2py is very light and quick, but it has less 3rd party libraries and support than Django or Flask.
If you're planning to extend your project after auth, I suggest to use Django for this project.
Anyway, If web2py is your must-go option, no problem and I can implement it in 3 days.
Looking forward to hearing from you soon.
Best Regards,
Bruno