def get_queue_class(config=None, queue_class=None):
    """
    Return queue class from config or from RQ settings, otherwise return DjangoRQ.
    If ``queue_class`` is provided, it takes priority.

    The full priority list for queue class sources:
    1. ``queue_class`` argument
    2. ``QUEUE_CLASS`` in ``config`` argument
    3. ``QUEUE_CLASS`` in base settings (``RQ``)
    """
    RQ = getattr(settings, 'RQ', {})
    if queue_class is None:
        queue_class = RQ.get('QUEUE_CLASS', DjangoRQ)
        if config:
            queue_class = config.get('QUEUE_CLASS', queue_class)

    if isinstance(queue_class, str):
        queue_class = import_attribute(queue_class)
    return queue_class

    Return queue class from config or from RQ settings, otherwise return DjangoRQ.
    If ``queue_class`` is provided, it takes priority.

    The full priority list for queue class sources:
    1. ``queue_class`` argument
    2. ``QUEUE_CLASS`` in ``config`` argument
    3. ``QUEUE_CLASS`` in base settings (``RQ``)
    
django_rq/queues.py