qiskit/dagcircuit/dagcircuit.py
def ancestors(self, node):
        """Returns set of the ancestors of a node as DAGNodes."""
        if isinstance(node, int):
            warnings.warn('Calling ancestors() with a node id is deprecated,'
                          ' use a DAGNode instead',
                          DeprecationWarning, 2)
            node = self._id_to_node[node]

        return nx.ancestors(self._multi_graph, node)
def ancestors(self, node):
        """Returns set of the ancestors of a node as DAGNodes."""
        if isinstance(node, int):
            warnings.warn('Calling ancestors() with a node id is deprecated,'
                          ' use a DAGNode instead',
                          DeprecationWarning, 2)
            node = self._id_to_node[node]

        return nx.ancestors(self._multi_graph, node)
Returns set of the ancestors of a node as DAGNodes.