multi-protocol url-based IO -- pure python kioslave-like module?

[Rob McMullen]

Wheel reinvention preemption question: is there an existing pure-
python library with functionality similar to KDE's kio/kioslave
implementation?  A multi-protocol, extensible library based on URLs
that abstracts directory listing and file read/write?  I'm looking to
use it in client code, not server, so it doesn't have to be
asynchronous like kio; ideally it would be small and only depend on
the standard python library.

Here's what I'm aware of:

* urllib2 doesn't handle opening URLs for writing, meaning that it's
incapable of supporting WebDAV or e.g. the fish:// protocol

* twisted is built to handle multiple protocols, but is an extremely
large package aiming to simplify low-level server and client code

* Boa Contstructor has something called Explorers which support
multiple protocols, but seems pretty tied to its gui implementation

* PyKDE can interface with the KDE shared libraries, but obviously
that's not pure python. (Or standalone or small. :)

* the somewhat related PEP-268 for WebDAV support, but that was
withdrawn.

My google-fu doesn't show much else.  Any pointers would be
appreciated!

Thanks,

Rob