@pimms.value<EOL><INDENT>def area_id_to_name(area_name_to_id):<DEDENT>
if area_name_to_id is None: return None<EOL>return pyr.pmap({v:k for (k,v) in six.iteritems(area_name_to_id)})<EOL>
mdl.area_id_to_name is a persistent map whose keys are area id's and whose values are the
associated area's name.