class Stage(models.Model):      _name = 'todo.task.stage'      _order = 'sequence,name'      # String fields:      name = fields.Char('Name', 40)      desc = fields.Text('Description')      state = fields.Selection(          [('draft','New'), ('open','Started'),('done','Closed')],          'State')      docs = fields.Html('Documentation')      # Numeric fields:      sequence = fields.Integer('Sequence')      perc_complete = fields.Float('% Complete', (3, 2))      # Date fields:      date_effective = fields.Date('Effective Date')      date_changed = fields.Datetime('Last Changed')      # Other fields:      fold = fields.Boolean('Folded?')      image = fields.Binary('Image')