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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _check_markers(task_ids, offset=10):
 """Returns a flag for markers being found for the task_ids. If all task ids have markers True will be returned. Otherwise it will return False as soon as a None result is hit. """


    shuffle(task_ids)
    has_errors = False

    for index in xrange(0, len(task_ids), offset):
        keys = [ndb.Key(FuriousAsyncMarker, id)
                for id in task_ids[index:index + offset]]

        markers = ndb.get_multi(keys)

        if not all(markers):
            logging.debug("Not all Async's complete")
            return False, None

        # Did any of the aync's fail? Check the success property on the
        # AsyncResult.
        has_errors = not all((marker.success for marker in markers))

    return True, has_errors