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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 centerOfMass(self):
 """Get the center of mass of actor. .. hint:: |fatlimb| |fatlimb.py|_ """

        cmf = vtk.vtkCenterOfMass()
        cmf.SetInputData(self.polydata(True))
        cmf.Update()
        c = cmf.GetCenter()
        return np.array(c)