We need a place to put code that manipulates our core data. That code could be invoked by a treemap view, a cloud_management view, an API call, or a manage.py command. Django's default structure has no place for such code. Some have suggested an extra level at the top with `app/` for your apps and `lib/` for such data manipulation code. We haven't gone that route and instead have been putting such code into `treemap` in various places. My proposal above was to make a formal place for such code in `treemap/helpers` (or `treemap/lib`).

A helper used in just one file can be an underscore method in that file, but if used in more than one file it should move to the helpers folder.

Over time we could move other files from `treemap` there as well (like maybe `ecobenefits.py, `search.py`, `DotDict.py`)