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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 graph(self):
 """ Returns MultiDiGraph from kihs. Nodes are helices and edges are kihs. """

        g = networkx.MultiDiGraph()
        edge_list = [(x.knob_helix, x.hole_helix, x.id, {'kih': x}) for x in self.get_monomers()]
        g.add_edges_from(edge_list)
        return g