Prints option value from the config.

        Args:
            config (configobj.ConfigObj): config to work on.
            section (str): section name.
            opt (str): option name.

def show(config, section, opt):
        """Prints option value from the config.

        Args:
            config (configobj.ConfigObj): config to work on.
            section (str): section name.
            opt (str): option name.
        """
        if section not in config.keys():
            raise ConfigError("section '{}' doesn't exist".format(section))

        if opt not in config[section].keys():
            raise ConfigError(
                "option '{}.{}' doesn't exist".format(section, opt)
            )

        logger.info(config[section][opt])