'Individual download thread that will download parts of the file from Glacier. Parts
to download stored in work queue.
Parts download to a temp dir with each part a separate file
:param job: Glacier job object
:param work_queue: A queue of tuples which include the part_number and
part_size
:param result_queue: A priority queue of tuples which include the
part_number and the path to the temp file that holds that
part\'s data.'

def __init__(self, job, worker_queue, result_queue, num_retries=5, time_between_retries=5, retry_exceptions=Exception):

    super(DownloadWorkerThread, self).__init__(worker_queue, result_queue)
    self._job = job
    self._num_retries = num_retries
    self._time_between_retries = time_between_retries
    self._retry_exceptions = retry_exceptions
