First, you'll need configs. You can clone the github.com/minimization/content-resolver-input repository and use the configs directory.
Or you can put your own configs to a local directory:
$ mkdir configs
$ vim configs/config.yml
See the config spec for reference.
For initial run, the script will download data from Content Resolver. This can take a minute.
$ mkdir output
$ ls configs # <--- this needs to have the configs. You can of course point to a different location.
$ ./eln_repo_split.py ./configs ./output
For repetitive runs, you can use the cashed data and save a lot of time.
$ ./eln_repo_split.py --use-cache ./configs ./output
A summary will be printed on the standard output and text files with the results will be in the ./output directory.