From the README at http://www.bitbucket.org/faheem/hg/src/tip/README.
hgwebproxy was written by Jesper Noehr ( firstname.lastname@example.org ), with minor modifications by Faheem Mitha ( email@example.com ). It uses code from https://bitbucket.org/jespern/cx/. Hgwebproxy uses Django as a proxy for hgweb. In other words, when the request is sent to hgweb, Django gets it and relays it to hgweb, and then intercepts the response from hgweb, and can do post-processing on it if necessary. This has two advantages. One, hgweb can be put behind Django auth. Secondly, this makes it possible to use Django templating with hgweb.
To try out this project, clone http://www.bitbucket.org/faheem/hg and read README at top level.
Is Available a new fork of faheem app, Django Hgwebproxy fully integrated to the django admin interfaces.