if (!!parserConf.version && parseInt(parserConf.version, 10) === 3) {
        commonkeywords = commonkeywords.concat(py3.keywords);
        commonBuiltins = commonBuiltins.concat(py3.builtins);
        var stringPrefixes = new RegExp("^(([rb]|(br))?('{3}|\"{3}|['\"]))", "i");
    } else {