Currently using the version that Windows has chosen as default (user double clicks on install.py), or the version that the IDLE is using (user right clicks and 'open with IDLE...').
Since there are multiple versions of python possible (ArcGIS 32bit and 64 bit, python 2.7/3.4 for Desktop/Pro as well as other user installed versions). this is tricky, yet critical.
The python interpreter seems to be built into ArcMap and ArcCatalog, (i.e. sys.executable returns arcmap.exe), however the sys.path includes components from the version being used.
Currently using the version that Windows has chosen as default (user double clicks on install.py), or the version that the IDLE is using (user right clicks and 'open with IDLE...'). Since there are multiple versions of python possible (ArcGIS 32bit and 64 bit, python 2.7/3.4 for Desktop/Pro as well as other user installed versions). this is tricky, yet critical.
The python interpreter seems to be built into ArcMap and ArcCatalog, (i.e. sys.executable returns arcmap.exe), however the sys.path includes components from the version being used.