update PYTHONPATH for sub-processes
In case a python process starts a sub-process (e.g. cpymad), it does not inherit the change sys.path
; in this case, the PYTHONPATH in the OS environment needs to be updated as well.
In case a python process starts a sub-process (e.g. cpymad), it does not inherit the change sys.path
; in this case, the PYTHONPATH in the OS environment needs to be updated as well.