public function balanceMulti($addresses, $tag = EtherscanAPIConf::TAG_LATEST) {
        if (is_array($addresses)) {
            $addresses = implode(",", $addresses);
        }

        return $this->request->exec([
            'module' => "account",
            'action' => "balancemulti",
            'address' => $addresses,
            'tag' => $tag
        ]);
    }