'Attempt to download a part of the archive from Glacier
Store the result in the result_queue
:param work:'

def _process_chunk(self, work):

    result = None
    for _ in range(self._num_retries):
        try:
            result = self._download_chunk(work)
            break
        except self._retry_exceptions as e:
            log.error('Exception    caught    downloading    part    number    %s    for    job    %s', work[0], self._job)
            time.sleep(self._time_between_retries)
            result = e
    return result
