[mod_python] PSP global variables

I'm building a PSP tutorial and can't find in the mod_python manual
any references to the global variables req, form and session as in
this article:

http://www.onlamp.com/pub/a/python/2004/02/26/python_server_pages.html

Are they unsupported features?

http://webpython.codepoint.net/mod_python_psp

Regards, Clodoaldo Pinto Neto