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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 default_mp_batchify_fn(data):
 """Collate data into batch. Use shared memory for stacking."""

    if isinstance(data[0], nd.NDArray):
        out = nd.empty((len(data),) + data[0].shape, dtype=data[0].dtype,
                       ctx=context.Context('cpu_shared', 0))
        return nd.stack(*data, out=out)
    elif isinstance(data[0], tuple):
        data = zip(*data)
        return [default_mp_batchify_fn(i) for i in data]
    else:
        data = np.asarray(data)
        return nd.array(data, dtype=data.dtype,
                        ctx=context.Context('cpu_shared', 0))