Return queue type most appropriate for runtime model.

    If we are using multiprocessing, that should be
    multiprocessing.Manager().Queue. If we are just using a
    single process, then use a normal queue type.

def _obtain_queue(num_jobs):
    """Return queue type most appropriate for runtime model.

    If we are using multiprocessing, that should be
    multiprocessing.Manager().Queue. If we are just using a
    single process, then use a normal queue type.
    """
    if _should_use_multiprocessing(num_jobs):
        return ReprQueue(multiprocessing.Manager().Queue())

    return ReprQueue(Queue())