public static function textBatch(Api\MtBatchTextSmsCreate $batch)
    {
        $fields = Serialize::_createBatchHelper($batch);

        $fields['type'] = 'mt_text';
        $fields['body'] = $batch->getBody();

        if (!empty($batch->getParameters())) {
            $fields['parameters'] = $batch->getParameters();
        }

        return Serialize::_toJson($fields);
    }