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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 _stmt_graph_add_edge(self, src, dst, **edge_labels):
 """ Add an edge in the statement dependence graph from a program location `src` to another program location `dst`. :param CodeLocation src: Source node. :param CodeLocation dst: Destination node. :param edge_labels: All labels associated with the edge. :returns: None """


        # Is that edge already in the graph ?
        # If at least one is new, then we are not redoing the same path again
        if src in self._stmt_graph and dst in self._stmt_graph[src]:
            return

        self._stmt_graph.add_edge(src, dst, **edge_labels)