Flask,Jinja2 + bootstrap + learn python functools.wraps
Flask just makes the dispatch and routing. Jinja templates are very close to smarty. You can make a site runing in a second. Also a benefit of using flask is that you have ready WSGI app that you can put on gevent or tornado.
If some of your output is prematurely truncated if you are behind HAProxy - check tornado keep alive settings. (not relevant but took me 2 days to figure it out)
This is essentially gives you the tools to get started and not much else. You don't want to have to reinvent protocols like Wsgi in order to run fast python code.
I don't want to have to work around a framework or have one get in the way. I would rather redo the work, knowing 100% what every line of code in my app is doing. Plus, large frameworks like Django don't even look like Python at times.
If you're intent on understanding 100% of your codebase, you should consider one of the single-file frameworks, like Bottle or Flask, and spend some time reading and understanding their code.