public static function get_by($kwargs)
{
if (isset($kwargs['user_email'])) {
$userid = get_user_id_from_string($kwargs['user_email']);
if ($userid === 0) {
throw new JsonableException(__("I don't know that email address", 'mtv'));
}
} else {
if (isset($kwargs['user_login'])) {
$userid = get_user_id_from_string($kwargs['user_login']);
if ($userid === 0) {
throw new JsonableException(__("I don't know that user name", 'mtv'));
}
} else {
throw new NotImplementedException();
}
}
$user = new static::$model(array('id' => $userid));
$user->fetch();
return $user;
}