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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 create_actor_tri(pts, tris, color, **kwargs):
 """ Creates a VTK actor for rendering triangulated surface plots. :param pts: points :type pts: vtkFloatArray :param tris: list of triangle indices :type tris: ndarray :param color: actor color :type color: list :return: a VTK actor :rtype: vtkActor """

    # Keyword arguments
    array_name = kwargs.get('name', "")
    array_index = kwargs.get('index', 0)

    # Create points
    points = vtk.vtkPoints()
    points.SetData(pts)

    # Create triangles
    triangles = vtk.vtkCellArray()
    for tri in tris:
        tmp = vtk.vtkTriangle()
        for i, v in enumerate(tri):
            tmp.GetPointIds().SetId(i, v)
        triangles.InsertNextCell(tmp)

    # Create a PolyData object and add points & triangles
    polydata = vtk.vtkPolyData()
    polydata.SetPoints(points)
    polydata.SetPolys(triangles)

    # Map poly data to the graphics primitives
    mapper = vtk.vtkPolyDataMapper()
    mapper.SetInputDataObject(polydata)
    mapper.SetArrayName(array_name)
    mapper.SetArrayId(array_index)

    # Create an actor and set its properties
    actor = vtk.vtkActor()
    actor.SetMapper(mapper)
    actor.GetProperty().SetColor(*color)

    # Return the actor
    return actor