code: public function copyAttributesFrom(SimpleXMLElement $src, $overwrite = true)
      {
          $dom = dom_import_simplexml($this);
  
          foreach (dom_import_simplexml($src)->attributes as $attr) {
              if ($overwrite
                  || !$dom->hasAttributeNS($attr->namespaceURI, $attr->nodeName)
              ) {
                  $dom->setAttributeNS($attr->namespaceURI, $attr->nodeName, $attr->nodeValue);
              }
          }
  
          return $this;
      }
docs: Copy all attributes from a node to current node
  
  @param    SimpleXMLElement $src Source node
  @param    bool $overwrite If TRUE, overwrite existing attributes.
  Otherwise, ignore duplicate attributes
  @return    SimpleDOM                        Current node