function setAllGroupsOnHomeCategory()
{
    $results = Group::getGroups(Configuration::get('PS_LANG_DEFAULT'));
    $groups = array();
    foreach ($results as $result) {
        $groups[] = $result['id_group'];
    }
    if (is_array($groups) && sizeof($groups)) {
        $category = new Category(1);
        $category->cleanGroups();
        $category->addGroups($groups);
    }
}