code: public function toNode(DOMDocument $document = null)
      {
          if (null === $document) {
              $document = new DOMDocument();
          }
  
          $node = $document->createElement('ShipFrom');
  
          if ($this->getCompanyName()) {
              $node->appendChild($document->createElement('CompanyName', $this->getCompanyName()));
          }
  
          if ($this->getAttentionName()) {
              $node->appendChild($document->createElement('AttentionName', $this->getAttentionName()));
          }
  
          $address = $this->getAddress();
          if (isset($address)) {
              $node->appendChild($address->toNode($document));
          }
  
          return $node;
      }
docs: @param null|DOMDocument $document
  
  @return DOMElement