atma2 is a simple web-framework that has most common features, digest authentication, http/1.1, xml based template system, asynchronous facilities (ajax), large file upload suport and fastcgi, it works on top of twisted networking core.

http://www.python.org/
developed and tested with version 2.4.4

http://twistedmatrix.com/
developed and tested with version 2.5.0