text: from collections import namedtuple
  from datetime import datetime
  
  from mongoengine import DateTimeField, Document, ObjectIdField, StringField
  
  
  _board_type = namedtuple('BoardType', 'id, display_name')
  
  
  class BoardType:
      PERSONAL = _board_type('personal', 'Personal')
  
  
  BOARD_TYPES = [BoardType.PERSONAL]
  
  
  class Board(Document):
  
      created = DateTimeField(required=True, default=datetime.utcnow)
      created_by = ObjectIdField(required=True)
      name = StringField(required=True, min_length=1, max_length=256)
      owner_id = ObjectIdField(required=True)
      type = StringField(required=True)
  