Creating a web service for Qualtrics written in Python on Google App Engine
I am familiar with Qualtrics but I will answer (b) first.
You can write a Python Web Service in a variety of ways, depending on your choice:

You could write a simple get handler
Use Google Cloud Endpoints
Use one of several Web Services Python libraries

Having said that, a quick glance at Qualtrics indicated that it required a RSS feed in the result format(I could be wrong). So what you will need to take care of while doing (b) is to ensure that it is in a format that Qualtrics understand and parses out the response format for you.
For e.g. if you have to return RSS, you could write your Python Web Service to return that data. Optionally, it can also take one or more parameters to fine tune the results.
Has anyone out there created a a.) web service for Qualtrics or b.) a Python web service on Google App Engine?
I need to build in some functionality to a Qualtrics survey that seems only a web service (in the Qualtrics Survey Flow) could do, like passing parameters to a web service then getting a response back. 
I've looked at GAE Protocol RPC, but I'm not quite sure if that's the right path. Qualtrics gave me a PHP code example but I don't know how to begin translating it to python and/or GAE.