Install following the instructions from this link. (Install with Voyager 2 kernels!)
The $ISISROOT environment variable must be added to Bash config file info.
The $NEPTUPY is also required: export NEPTUPY=/route/to/your/local/copy/from/this/repo
XPA service is required in order to correct functionality with NeptuPy, sure this environment variable is added to your Bash config file:
export XPA_METHOD=local