code: def _validate(self, value):
          
          _LOGGER.info('validate: Got type %s', type(value))
          if value is not None and not isinstance(value, client.Flow):
              raise TypeError(
                  'Property {0} must be convertible to a flow '
                  'instance; received: {1}.'.format(self._name, value))
docs: Validates a value as a proper Flow object.
  
          Args:
              value: A value to be set on the property.
  
          Raises:
              TypeError if the value is not an instance of Flow.