public function formatAccessRule(Model\AccessRule $model)
{
$rule = $this->formatAccessRuleArray(['id' => $model->getId(), 'users' => $model->getUsers(), 'group' => $model->getGroup(), 'resources' => $model->getResources()]);
return <<<RULE
<?xml version="1.0" encoding="UTF-8"?>
<imbo>
{$rule}
</imbo>
RULE;
}