I thought this would be 5 ms. If it is 5 seconds I am absolute against this solution. OpenSlides runs in one thread. That means, that it pauses not only for the one user, but for all users. Including serving of static files.

Have a look at the Tornado documentation, if you really need this 5 seconds:
http://www.tornadoweb.org/en/branch2.1/ioloop.html