Private method to check section and option types

def _check_section_option(self, section, option):
        """
        Private method to check section and option types
        """
        if section is None:
            section = self.DEFAULT_SECTION_NAME
        elif not is_text_string(section):
            raise RuntimeError("Argument 'section' must be a string")
        if not is_text_string(option):
            raise RuntimeError("Argument 'option' must be a string")
        return section