public function Export(array $channelIDs = array(), $fileFormat = \ElasticEmailEnums\ExportFileFormats::Csv, $compressionFormat = \ElasticEmailEnums\CompressionFormat::None, $fileName = null) {
        return $this->sendRequest('campaign/export', array(
                    'channelIDs' => (count($channelIDs) === 0) ? null : join(';', $channelIDs),
                    'fileFormat' => $fileFormat,
                    'compressionFormat' => $compressionFormat,
                    'fileName' => $fileName
        ));
    }