code: def send_file_external(self, url_json, chunk):
          
          http_verb = url_json['http_verb']
          host = url_json['host']
          url = url_json['url']
          http_headers = url_json['http_headers']
          resp = self._send_file_external_with_retry(http_verb, host, url, http_headers, chunk)
          if resp.status_code != 200 and resp.status_code != 201:
              raise ValueError("Failed to send file to external store. Error:" + str(resp.status_code) + host + url)
docs: Send chunk to external store specified in url_json.
          Raises ValueError on upload failure.
          :param data_service: data service to use for sending chunk
          :param url_json: dict contains where/how to upload chunk
          :param chunk: data to be uploaded