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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 get_structure_with_nodes(self):
 """ Get the modified structure with the voronoi nodes inserted. The species is set as a DummySpecie X. """

        new_s = Structure.from_sites(self.structure)
        for v in self.vnodes:
            new_s.append("X", v.frac_coords)
        return new_s