a worker used by :func:`run_parallel`

def _reliure_worker(wnum, Qin, Qout, pipeline, options={}):
    """ a worker used by :func:`run_parallel`
    """
    #pipeline = get_pipeline()
    logger = logging.getLogger("reliure.run_parallel.worker#%s" % wnum)
    logger.debug("worker created")
    if options is None:
        options = {}
    while True:
        chunk = Qin.get() # get an element (and wait for it if needed)
        logger.debug("Get %s elements to process" % len(chunk))
        res = [output for output in pipeline(chunk, **options)]
        logger.debug("processing done, results len = %s" % len(res))
        Qout.put(res)
        Qin.task_done()