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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 del_edge(self, edge):
 """ Remove an edge from the graph. @type edge: tuple @param edge: Edge. """

        u, v = edge
        self.node_neighbors[u].remove(v)
        self.del_edge_labeling((u, v))  
        if (u != v):
            self.node_neighbors[v].remove(u)
            self.del_edge_labeling((v, u))