iOS How to access it?

Though not started working on the below given scenario but gathering info before starting work:
Using iPhone, I have to access a python web service hosted on google app engine.
1] Does the web service needs to be a WSGI application [Correct me, if appropriate as I am a fresher at python side]?
2] Web services created in microsoft .net needs to be converted to REST before accessing them from iphone, so do i need to convert my python web service too into REST enabled?

Thanks for a quick reply
I am totally new at python side and struggling for a way to create even for a simple web service using python. Can you tell me a way to create one for a google app engine or any relevant simple link for the same?
I have read the google App engine "Getting started guide" but it nowhere mentions about web service and just talks about wsgi applications so I am a little confused in this too. If I create a wsgi application that doesn't expose any user interface using google app engine sdk, will it be called a web service or not?