Missing yaml package in (NPL) on cheyenne so get_extrn_ics fails

Hi-

I'm trying to run the develop branch config.community.sh on cheyenne, and the python virtual environment doesn't exactly match up with what is in the develop branch docs. When I continue to running a workflow, get_extrn_ics fails because the yaml package is not included in the (NPL) virtual environment.

Here are the steps I took to get this error:

1. I ran 'module load wflow_cheyenne'

(this tells me to run 'ncar_pylib /glade/p/ral/jntp/UFS_SRW_app/ncar_pylib/regional_workflow'

2. I ran 'ncar_pylib /glade/p/ral/jntp/UFS_SRW_app/ncar_pylib/regional_workflow' as instructed

(this tells me that I'm now using NPL venv at: /glade/p/ral/jntp/UFS_SRW_app/ncar_pylib/regional_workflow)

(NOTE that my prompt says '(NPL)' and not '(regional_workflow)' as it says it should in the docs. I tried to run conda to load regional_workflow, as it says to in the docs when your prompt doesn't say '(regional_workflow)', but conda is not available on cheyenne)

3. 'pip list' shows a long list of python packages for (NPL), including PyYAML 5.1.3

4. './generate_FV3LAM_wflow.sh' from regional_workflow

5. 'cd $EXPTDIR' and './launch_FV3LAM_wflow.sh'
produces the following output:

Please do the following to activate ncar_pylib:
       > ncar_pylib /glade/p/ral/jntp/UFS_SRW_app/ncar_pylib/regional_workflow
/glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/bash_utils/filesys_cmds_vrfy.sh: line 68: BASH_SOURCE[2]: unbound variable

6. log/get_extrn_ics_2019061500.log shows:

python3 -u /glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/retrieve_data.py   --debug   --anl_or_fcst anl   --config /glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/templates/data_locations.yml   --cycle_date 2019061500   --data_stores disk    --external_model FV3GFS   --fcst_hrs 0   --output_path /glade/scratch/paddy/expt_dirs/test_RRFS_CONUS_13km/2019061500/FV3GFS/for_ICS   --summary_file extrn_mdl_var_defns.sh      --file_type grib2   --file_templates gfs.pgrb2.0p25.f000   --input_file_path /glade/p/ral/jntp/UFS_SRW_App/develop/staged_extrn_mdl_files/FV3GFS/'
+ python3 -u /glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/retrieve_data.py --debug --anl_or_fcst anl --config /glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/templates/data_locations.yml --cycle_date 2019061500 --data_stores disk --external_model FV3GFS --fcst_hrs 0 --output_path /glade/scratch/paddy/expt_dirs/test_RRFS_CONUS_13km/2019061500/FV3GFS/for_ICS --summary_file extrn_mdl_var_defns.sh --file_type grib2 --file_templates gfs.pgrb2.0p25.f000 --input_file_path /glade/p/ral/jntp/UFS_SRW_App/develop/staged_extrn_mdl_files/FV3GFS/
Traceback (most recent call last):
  File "/glade/scratch/paddy/ufs-srweather-app-develop/regional_workflow/ush/retrieve_data.py", line 38, in <module>
    import yaml
ModuleNotFoundError: No module named 'yaml'
+ print_err_msg_exit 'Call to retrieve_data.py failed with a non-zero exit status.

I'm wondering if I have failed to load the proper python virtual environment, or if I have the right venv and it is missing yaml for some reason. Has anyone else run across a similar problem?

Thank you very much, 

-Paddy McCarthy.