Python build error while building selenium webdriv

I'm attempting to get into some opensource projects, and as a QA engineer, have been looking at Appium and Selenium.

Situation: Windows 10
Appium: cloned repo, built successfully
Selenium: cloned, but having troubles.
Installed: Java, JDK, python 3.6, Ruby, Rake gem.
Error, I use go + a target, eg 'go build', 'go' or 'go firefox'. However I'm always getting the following error:

The error:

C:\Users\Mark\selenium>go build
(in C:/Users/Mark/selenium)
python C:/Users/Mark/selenium/buck-out/crazy-fun/7c1417f319649e9fd58fd3f97f36f42c870b1790/buck.pex kill
Traceback (most recent call last):
  File "C:\Users\Mark\AppData\Local\Programs\Python\Python36-32\lib\runpy.py", line 193, in _run_module_as_main
    "__main__", mod_spec)
  File "C:\Users\Mark\AppData\Local\Programs\Python\Python36-32\lib\runpy.py", line 85, in _run_code
    exec(code, run_globals)
  File "C:\Users\Mark\selenium\buck-out\crazy-fun\7c1417f319649e9fd58fd3f97f36f42c870b1790\buck.pex\__main__.py", line 25, in <module>
  File "C:\Users\Mark\selenium\buck-out\crazy-fun\7c1417f319649e9fd58fd3f97f36f42c870b1790\buck.pex\.bootstrap\_pex\pex_bootstrapper.py", line 94, in bootstrap_pex
  File "C:\Users\Mark\selenium\buck-out\crazy-fun\7c1417f319649e9fd58fd3f97f36f42c870b1790\buck.pex\.bootstrap\_pex\finders.py", line 218, in register_finders
AttributeError: module 'importlib._bootstrap' has no attribute 'FileFinder'
go aborted!

I'm unable to find anything similar online aside from one post suggesting an issue with older versions of Python potentially. However I've just downloaded the latest, so wouldn't expect an issue...

The Selenium build scripts utilised here (either crazyfunbuild or buckd depending on setup and tools installed) uses Python 2.7 (at time of writing).

A downgrade from 3.6 to 2.7 solved my (python) issues at least.