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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 polydata(self, transformed=True):
 """ Returns the ``vtkPolyData`` of an ``Actor``. .. note:: If ``transformed=True`` returns a copy of polydata that corresponds to the current actor's position in space. .. hint:: |quadratic_morphing| |quadratic_morphing.py|_ """

        if not transformed:
            if not self.poly:
                self.poly = self.GetMapper().GetInput()  # cache it for speed
            return self.poly
        M = self.GetMatrix()
        if utils.isIdentity(M):
            if not self.poly:
                self.poly = self.GetMapper().GetInput()  # cache it for speed
            return self.poly
        # if identity return the original polydata
        # otherwise make a copy that corresponds to
        # the actual position in space of the actor
        transform = vtk.vtkTransform()
        transform.SetMatrix(M)
        tp = vtk.vtkTransformPolyDataFilter()
        tp.SetTransform(transform)
        tp.SetInputData(self.poly)
        tp.Update()
        return tp.GetOutput()