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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 hdf5_to_dict(filepath, group='/'):
 """load the content of an hdf5 file to a dict. # TODO: how to split domain_type_dev : parameter : value ? """

    if not h5py.is_hdf5(filepath):
        raise RuntimeError(filepath, 'is not a valid HDF5 file.')

    with h5py.File(filepath, 'r') as handler:
        dic = walk_hdf5_to_dict(handler[group])
    return dic