[Twisted-Python] Light-est-weight http authentication

I have a backend Twisted application with a front end in Django. Some of their communication is via web services. Currently they are deployed on the same box but may be separated in future. I want to enforce some basic authentication on the web services, so some lightweight http header authentication looks best. I've found the twisted.web.guard api, but it seems to be more heavyweight than I require (e.g. running up a Portal). Given the breadth of the Twisted apis, I'm confident I wouldn't have to hand-craft something to check the auth header myself. What do you guys suggest? Thanks Brad