public function getAttributeNS($namespaceURI, $localName): ?string
    {
        if ($this->ownerDocument
            && $namespaceURI === XliffFile::XLIFF_NS
            && $this->ownerDocument->isDefaultNamespace(XliffFile::XLIFF_NS)) {
            return \call_user_func_array(['parent', 'getAttribute'], \array_slice(\func_get_args(), 1));
        }

        return \call_user_func_array(['parent', 'getAttributeNS'], \func_get_args());
    }