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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 make_worker_pool( processes=None, initializer=None, initializer_kwargs_per_process=None, max_tasks_per_worker=None):
 """ Convenience wrapper to create a multiprocessing.Pool. This function adds support for per-worker initializer arguments, which are not natively supported by the multiprocessing module. The motivation for this feature is to support allocating each worker to a (different) GPU. IMPLEMENTATION NOTE: The per-worker initializer arguments are implemented using a Queue. Each worker reads its arguments from this queue when it starts. When it terminates, it adds its initializer arguments back to the queue, so a future process can initialize itself using these arguments. There is one issue with this approach, however. If a worker crashes, it never repopulates the queue of initializer arguments. This will prevent any future worker from re-using those arguments. To deal with this issue we add a second 'backup queue'. This queue always contains the full set of initializer arguments: whenever a worker reads from it, it always pushes the pop'd args back to the end of the queue immediately. If the primary arg queue is ever empty, then workers will read from this backup queue. Parameters processes : int Number of workers. Default: num CPUs. initializer : function, optional Init function to call in each worker initializer_kwargs_per_process : list of dict, optional Arguments to pass to initializer function for each worker. Length of list must equal the number of workers. max_tasks_per_worker : int, optional Restart workers after this many tasks. Requires Python >=3.2. Returns ------- multiprocessing.Pool """


    if not processes:
        processes = cpu_count()

    pool_kwargs = {
        'processes': processes,
    }
    if max_tasks_per_worker:
        pool_kwargs["maxtasksperchild"] = max_tasks_per_worker

    if initializer:
        if initializer_kwargs_per_process:
            assert len(initializer_kwargs_per_process) == processes
            kwargs_queue = Queue()
            kwargs_queue_backup = Queue()
            for kwargs in initializer_kwargs_per_process:
                kwargs_queue.put(kwargs)
                kwargs_queue_backup.put(kwargs)
            pool_kwargs["initializer"] = worker_init_entry_point
            pool_kwargs["initargs"] = (
                initializer, kwargs_queue, kwargs_queue_backup)
        else:
            pool_kwargs["initializer"] = initializer

    worker_pool = Pool(**pool_kwargs)
    print("Started pool: %s" % str(worker_pool))
    pprint(pool_kwargs)
    return worker_pool