provides a fallback_on_none_attribute field attribute, allowing to specify default value for attributes of *existing* entities
"""
:organization: Logilab
:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
"""
support_entities = {'Card': True, 'Affaire': True, 'State': True}
support_relations = {'in_state': True, 'documented_by': True, 'multisource_inlined_rel': True}