Thanks for reporting this! Yeah, there was this forum thread from a year ago:
I just a quick Google for “cannot import name ‘DataController’” and got lucky!
So… I do think we’re loading things in the wrong order. I’ve had a little back burner project where I’m trying to understand why Deadline after Python 3 ends up getting confused by libraries that aren’t our own. So far my theory is that we load up Python.net before we override the default search paths and before we may have been doing the opposite. I’m going to add both forum threads as data points on that ticket for when I can revisit it.