Associating Python Automated tests to Test Cases in Visual Studio Team Services

I am working using Visual Studio Team Services for Backlog/test management. I have a Python project checked into source control within Visual Studio Online and this contains Selenium test cases. These test cases are recognised as unittests within Python Tools for Visual Studio in a connected Visual Studio 2015 instance, and they run successfully from there.

I'd like to be able to associate these tests as automated test cases within the TEST module to allow us to replace the existing manual coverage and automatically feed in the results to the test cases. Is it possible to link the automated test cases back to the tests in the TEST module, and if so, how is it done?

At present, the automated test fields in the test case are disabled - how can these be setup to run the python based scripts?