The /path/to/repo/www/chapter_08/property/forms.py file represents a module containing a form to capture room type information that needs a set of multiple check boxes for room and bed types. The actual lists of types are drawn from common collection documents under the roomTypes and bedTypes keys. We use the CommonService domain service class to perform lookups for both keys. Each document in the common collection has two fields: key and value. The information contained in the value field is in the form of a list.
We also need a template to match the form. The Django template language is used, and provides safety measures in case of an error. The complete form template is located at /path/to/repo/www/chapter_08/templates/property_room_type.html.