Re: “latest python version” — note that many of the Python scripts in Rosetta are written for Python2, not Python3, so you may need to run them with `python2.7` rather than `python3.6`.
(If your OS is one of the few which flouts the Python standard and aliases plain `python` to a Python3 version, you may need to explcitly reference `python2.7` rather than plain `python`. — I don’t think this is the case for Macs, though.)