def METHOD_NAME(tmp_path):
    outfilename = tmp_path / "vu_tide_hourly_p0.dfs0"
    ds = mikeio.read("tests/testdata/vu_tide_hourly.dfs1")
    assert ds.n_elements > 1
    ds_0 = ds.isel(0, axis="space")
    assert ds_0.n_elements == 1
    ds_0_0 = ds_0.isel(0)
    assert ds_0_0.n_timesteps == 1
    ds_0_0.to_dfs(outfilename)
    dsnew = mikeio.read(outfilename)
    assert dsnew.n_timesteps == 1