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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 delaunay2D(plist, mode='xy', tol=None):
 """ Create a mesh from points in the XY plane. If `mode='fit'` then the filter computes a best fitting plane and projects the points onto it. .. hint:: |delaunay2d| |delaunay2d.py|_ """

    pd = vtk.vtkPolyData()
    vpts = vtk.vtkPoints()
    vpts.SetData(numpy_to_vtk(plist, deep=True))
    pd.SetPoints(vpts)
    delny = vtk.vtkDelaunay2D()
    delny.SetInputData(pd)
    if tol:
        delny.SetTolerance(tol)
    if mode=='fit':
        delny.SetProjectionPlaneMode(vtk.VTK_BEST_FITTING_PLANE)
    delny.Update()
    return Actor(delny.GetOutput())