def finalize_worker():
    """Finalize workers
    Python's multiprocessing pool will not call atexit function when close
    """
    global SAMPLER_POOL
    if SAMPLER_POOL is not None:
        SAMPLER_POOL.close()
Finalize workers
    Python's multiprocessing pool will not call atexit function when close
    
python/dgl/distributed/dist_context.py