Thanks, @tinkergnome!
Yes, the problem is line 58 in um3api.py. For some reason os.getlogin() does not work on my Linux systems, so I had to change it to use pwd.
>>> os.getlogin()Traceback (most recent call last): File "", line 1, in FileNotFoundError: [Errno 2] No such file or directory
Do you know of a more platform agnostic method?