def METHOD_NAME(data_map, *args):
    '''Save map of numpy arrays to hdf5 file.'''
    # Parse args.
    if len(args) == 1:
        path = args[0]
    elif len(args) == 2:
        dir_path, file_name = args
        path = os.path.join(dir_path, file_name)
    else:
        raise Exception("specialize for len(args) == %d." % len(args))
    # Save data.
    if not os.path.isfile(path):
        f = h5py.File(path, "w")
        for k, v in data_map.items():
            f.create_dataset(k, data=v)
        f.close()
    return path