qiskit/dagcircuit/dagcircuit.py
def _make_pred_succ_maps(self, node):
        """Return predecessor and successor dictionaries.

        Args:
            node (DAGNode): reference to multi_graph node

        Returns:
            tuple(dict): tuple(predecessor_map, successor_map)
                These map from wire (Register, int) to predecessor (successor)
                nodes of n.
        """

        pred_map = {e[2]['wire']: e[0] for e in
                    self._multi_graph.in_edges(nbunch=node, data=True)}
        succ_map = {e[2]['wire']: e[1] for e in
                    self._multi_graph.out_edges(nbunch=node, data=True)}
        return pred_map, succ_map
def _make_pred_succ_maps(self, node):
        """Return predecessor and successor dictionaries.

        Args:
            node (DAGNode): reference to multi_graph node

        Returns:
            tuple(dict): tuple(predecessor_map, successor_map)
                These map from wire (Register, int) to predecessor (successor)
                nodes of n.
        """

        pred_map = {e[2]['wire']: e[0] for e in
                    self._multi_graph.in_edges(nbunch=node, data=True)}
        succ_map = {e[2]['wire']: e[1] for e in
                    self._multi_graph.out_edges(nbunch=node, data=True)}
        return pred_map, succ_map
Return predecessor and successor dictionaries.

        Args:
            node (DAGNode): reference to multi_graph node

        Returns:
            tuple(dict): tuple(predecessor_map, successor_map)
                These map from wire (Register, int) to predecessor (successor)
                nodes of n.