/**
  * Get Invoice handle by number
  *
  * @param integer $no
  * @return null|object
  */
 public function getHandle($no)
 {
     if (is_object($no) and isset($no->Id)) {
         return $no;
     }
     @($result = $this->client->Invoice_FindByNumber(['number' => $no])->Invoice_FindByNumberResult);
     if ($result) {
         return $result;
     }
     return null;
 }