Hi,
I started a new project that implements decrypting and parsing of OTP values in Python:
http://code.google.com/p/yubikey-python/. I had a good look at the PHP, Java and C libraries that already implement this. In the near future I will add a Django authentication backend to this project. The decrypting and parsing won't depend on it though, so you can use it in any Python project. I welcome others to add authentication for other Python projects. If you find any issues or have suggestions, please post it to the Google Code project.
Thanks,
Rudolph Froger