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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 mergeActors(actors, tol=0):
 """ Build a new actor formed by the fusion of the polydatas of input objects. Similar to Assembly, but in this case the input objects become a single mesh. .. hint:: |thinplate_grid| |thinplate_grid.py|_ """

    polylns = vtk.vtkAppendPolyData()
    for a in actors:
        polylns.AddInputData(a.polydata())
    polylns.Update()
    pd = polylns.GetOutput()
    return Actor(pd)