Standard\Controllers\UsersController::upsertGroupAction PHP Method

    public function upsertGroupAction($id = null)
    {
        $data = [];
        if ($id) {
            $group = Gatekeeper::findGroupById($id);
            if (!$group) {
                $this->flasher->error('Group with ID ' . $id . ' not found!');
                $this->redirect('/users/groups');
            }
            $data['group'] = $group;
        }
        echo $this->twig->render('users/groups/upsert.twig', $data);
    }