code: def kbtype(self, value):
          
          if value is None:
              # set the default value
              return
          # or set one of the available values
          kbtype = value[0] if len(value) > 0 else 'w'
          if kbtype not in ['t', 'd', 'w']:
              raise ValueError('unknown type "{value}", please use one of \
                               following values: "taxonomy", "dynamic" or \
                               "written_as"'.format(value=value))
          self._kbtype = kbtype
docs: Set kbtype.