XPT is a general-purpose XML Preprocessor with facilitates easy interfacing with Python. It's initial context was within DocBook 5 projects, but it is not intented to be restricted to that context.
A tool/library is being build for manpage extraction from source files. XPT bindings are used to insert manpages into processed DocBook 5 output.
Sources can be download from SourceForge, where the SVN repository holds the most recent code. Ubuntu pre-built packages are automatically build on Lauchpad (https://launchpad.net/xml-xpt) from the SourceForge SVN repository each time it gets updated.
Recent documentation (and showcase) can be found at http://xml-xpt.sourceforge.net/docu/. Note that this is from the development branch, so things are changing often there.