def __PrintMessageCommentLines(self, message_type):
        """Print the description of this message."""
        description = message_type.description or '%s message type.' % (
            message_type.name)
        width = self.__printer.CalculateWidth() - 3
        for line in textwrap.wrap(description, width):
            self.__printer('// %s', line)
        PrintIndentedDescriptions(self.__printer, message_type.enum_types,
                                  'Enums', prefix='// ')
        PrintIndentedDescriptions(self.__printer, message_type.message_types,
                                  'Messages', prefix='// ')
        PrintIndentedDescriptions(self.__printer, message_type.fields,
                                  'Fields', prefix='// ')
Print the description of this message.