/**
  * Create Xml Message
  * @param SEPA\GroupHeader $setGroupHeader
  * @return SEPA\Message
  */
 public static function createXMLMessage(\SEPA\GroupHeader $setGroupHeader = null)
 {
     $message = new \SEPA\Message();
     //set to Message Group Header
     if (!empty($setGroupHeader)) {
         $message->setMessageGroupHeader($setGroupHeader);
     }
     return $message;
 }