'Extracts indexable attributes from an Answer.'

@classmethod
def extract_document(cls, obj_id, obj=None):

    fields = ['id', 'created', 'user_id', 'locale']
    if (obj is None):
        model = cls.get_model()
        obj_dict = model.objects.values(*fields).get(pk=obj_id)
    else:
        obj_dict = dict(((field, getattr(obj, field)) for field in fields))
    d = {}
    d['id'] = obj_dict['id']
    d['model'] = cls.get_mapping_type_name()
    d['indexed_on'] = int(time.time())
    d['created'] = obj_dict['created']
    d['locale'] = obj_dict['locale']
    d['creator_id'] = obj_dict['user_id']
    return d
