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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 update_coordinates(self, points, mesh=None, render=True):
 """ Updates the points of the an object in the plotter. Parameters points : np.ndarray Points to replace existing points. mesh : vtk.PolyData or vtk.UnstructuredGrid, optional Object that has already been added to the Plotter. If None, uses last added mesh. render : bool, optional Forces an update to the render window. Default True. """

        if mesh is None:
            mesh = self.mesh

        mesh.points = points

        if render:
            self._render()