    line0 = vtkLine()
    line0.GetPointIds().SetId(0, 0)  # the second 0 is the index of the Origin in linesPolyData's points
    line0.GetPointIds().SetId(1, 1)  # the second 1 is the index of P0 in linesPolyData's points

    # Create the second line (between Origin and P1)
    line1 = vtkLine()
    line1.GetPointIds().SetId(0, 0)  # the second 0 is the index of the Origin in linesPolyData's points
    line1.GetPointIds().SetId(1, 2)  # 2 is the index of P1 in linesPolyData's points

    # Create a vtkCellArray container and store the lines in it
    lines = vtkCellArray()
--
    line = vtkLine()
    for i in range(0, number_of_vertices):
        line.GetPointIds().SetId(i, i)

    ug = vtkUnstructuredGrid()
    ug.SetPoints(points)
--
        line = vtkLine()
        line.GetPointIds().SetId(0, i)
        line.GetPointIds().SetId(1, i + 1)
        lines.InsertNextCell(line)

    # Create a polydata to store everything in
--
            line = vtkLine()
            line.GetPointIds().SetId(0, pt_id)
            line.GetPointIds().SetId(1, pt_id + 1)
            lines.InsertNextCell(line)

    polydata = vtkPolyData()
--
        line = vtkLine()
        line.GetPointIds().SetId(0, i)
        line.GetPointIds().SetId(1, i + 1)
        lines.InsertNextCell(line)

    # Create a polydata to store everything in.
--
    line1 = vtkLine()
    line1.GetPointIds().SetId(0, 0)
    line1.GetPointIds().SetId(1, 1)

    # Create line2
    line2 = vtkLine()
    line2.GetPointIds().SetId(0, 2)
    line2.GetPointIds().SetId(1, 3)

    # Create a cellArray containing the lines
    lines = vtkCellArray()
--
    line = vtkLine()
    line.GetPointIds().SetId(0, 0)
    line.GetPointIds().SetId(1, 1)
    lines.InsertNextCell(line)
    line.GetPointIds().SetId(0, 1)
    line.GetPointIds().SetId(1, 2)
