I believe Microsoft advises against looking at the registry to find
these things, and advocates the use of SHGetFolder instead:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/apcompat/apcompat/use_the_application_programming_interface_to_locate_special_folders.asp

As for naming things: I guess an object ShellFolders in ntpath might
work fine, with (computed) attributes Desktop, Documents, etc (according
to the FOLDERID_ symbolic constants of the API).

OTOH, this is entirely ad-hoc, as tons of other Windows API is *not*
directly exposed to Python, so it's questionable why this one
specifically deserves being supported.

The patch has no documentation.