Best library to log into a webite and interact with it in Python?

This is an often asked question, yet the answers seem to be varied and I have specific requirements so I thought I'd ask anyways.

I want to go to a specific webpage, click on a log-in button that will redirect me to somewhere else, enter the log-in information - this should lead to me returning to the page I first arrived on - then clicking on some buttons. That's it.

I've seen a number of libraries recommended (urllib/urllib2,urllib3,requests,splinter/selenium) and I'm not sure what to pick. I want to login, I think every one of those can do it, requests seems to be the easiest, I want to click on buttons, know I can do that in selenium/splinter not sure about the others, want to be redirected after logging in which I think means cookies need to be saved, is that done automatically? I don't know.