code: def FoldValue(self, value):
      
      if value is False and self._data_type_definition.false_value is not None:
        return self._data_type_definition.false_value
  
      if value is True and self._data_type_definition.true_value is not None:
        return self._data_type_definition.true_value
  
      raise ValueError('No matching True and False values')
docs: Folds the data type into a value.
  
      Args:
        value (object): value.
  
      Returns:
        object: folded value.
  
      Raises:
        ValueError: if the data type definition cannot be folded into the value.