public function getInstancePoolKeySnippet($pkphp)
    {
        $pkphp = (array) $pkphp; // make it an array if it is not.
        $script = "";
        if (count($pkphp) > 1) {
            $script .= "serialize(array(";
            $i = 0;
            foreach ($pkphp as $pkvar) {
                $script .= ($i++ ? ', ' : '') . "(string) $pkvar";
            }
            $script .= "))";
        } else {
            $script .= "(string) " . $pkphp[0];
        }

        return $script;
    }