This is not what an interview at Disqus is like. We interview you like we work. This means you are going to code and you are going to lead a design discussion.
Coding is done on a computer you bring with your tools in a language you know. You get to use the Internet to looks stuff up, you know, just like you can when you are really doing your job. And the questions we ask are problems we have had to solve at work.
The design discussion is collaborative, the interviewer is an active part of the discussion playing a sort of devil's advocate.
If this seems like a process you would like, we have a bunch of python positions open right now, check them out here: http://grnh.se/vj71bo