silverstripe-framework/tests/php/Forms/CheckboxSetFieldTest/Tag.php

<?php

namespace SilverStripe\Forms\Tests\CheckboxSetFieldTest;

use SilverStripe\Dev\TestOnly;
use SilverStripe\ORM\DataObject;

class Tag extends DataObject implements TestOnly
{
    private static $table_name = 'CheckboxSetFieldTest_Tag';

    private static $belongs_many_many = [
        'Articles' => Article::class
    ];
}