public function startImportTask(ImportTask $it, $file_data)
    {
        $url = $this->service_url . '/import' . '?' . Util::query_suffix($it->queryData());
        $data = $this->service->prepAndSend($url, array(200, 201), 'POST', $file_data, true, 'application/zip', 'application/json');
        return TaskState::createFromJSON(json_decode($data));
    }