#concrete5 #5.7 Example of override config values from package

controller.php

<?php
namespace Concrete\Package\JapaneseCommunity;

use Config;

defined('C5_EXECUTE') or die('Access Denied.');

class Controller extends \Concrete\Core\Package\Package {

    protected $pkgHandle = 'japanese_community';
    protected $appVersionRequired = '5.7.0';
    protected $pkgVersion = '0.0.1';
    
    public function getPackageDescription()
    {
        return t('Japanese Community Package');
    }
    
    public function getPackageName()
    {
        return t('Japanese Community Package');
    }
    
    public function on_start()
    {
        Config::set('concrete.urls.newsflow', 'http://concrete5-japan.org');
    }

}

Do you have any idea about clear whole value inside a config file?