    reader = vtkDataSetReader()
    reader.SetFileName(fileName)

    # Create the scene.
    # We generate a whole bunch of planes which correspond to
    # the geometry in the analysis; tables, bookshelves and so on.
--
    reader = vtkDataSetReader()
    reader.SetFileName(fileName)
    reader.Update()

    # Now we will generate a single streamline in the data. We select the
    # integration order to use (RungeKutta order 4) and associate it with
