case.cmpgen_namelists is a script in CIMEROOT/scripts/Tools.
$ ./case.cmpgen_namelists --help usage: case.cmpgen_namelists [-h] [-d] [-v] [-s] [-c] [-g] [--compare-name COMPARE_NAME] [--generate-name GENERATE_NAME] [--baseline-root BASELINE_ROOT] [caseroot] case.cmpgen_namelists - perform namelist baseline operations (compare, generate, or both) for this case. positional arguments: caseroot Case directory for which namelists are compared/generated. Default is current directory. options: -h, --help show this help message and exit -d, --debug Print debug information (very verbose) to file /home/titters/devel/E3SM/cime/master/scripts/Tools/case.cmpgen_namelists.log -v, --verbose Add additional context (time and file) to log messages -s, --silent Print only warnings and error messages -c, --compare Force a namelist comparison against baselines. Default is to follow the case specification. -g, --generate Force a generation of namelist baselines. Default is to follow the case specification. --compare-name COMPARE_NAME Force comparison to use baselines with this name. Default is to follow the case specification. --generate-name GENERATE_NAME Force generation to use baselines with this name. Default is to follow the case specification. --baseline-root BASELINE_ROOT Root of baselines. Default is the case's BASELINE_ROOT.