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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 arrays_to_hdf5(filename="cache.hdf5"):
 """Returns registry for serialising arrays to a HDF5 reference."""

    return Registry(
        types={
            numpy.ndarray: SerNumpyArrayToHDF5(filename, "cache.lock")
        },
        hooks={
            '<ufunc>': SerUFunc()
        },
        hook_fn=_numpy_hook
    )