protected function createSiteAdminGroup()
    {
        $sitePerimeter = $this->createPerimeter(SiteInterface::ENTITY_TYPE, array(
            $this->getReference('site2')->getSiteId()
        ));

        $sadmin2 = new Group();
        $sadmin2->addLabel('en', 'Site admin demo');
        $sadmin2->addLabel('fr', 'Admin site demo');
        $sadmin2->setSite($this->getReference('site2'));
        $sadmin2->addRole(ContributionRoleInterface::SITE_ADMIN);
        $sadmin2->addPerimeter($sitePerimeter);

        return $sadmin2;
    }