def nodesDisconnected(self, fromDagNode, toDagNode):
        nodesAffected = list()
        nodesAffected = nodesAffected + self.dagNodeDisconnected(fromDagNode)
        self.dag.disconnectNodes(fromDagNode, toDagNode)

        # A few refreshes
        self.updateScenegraph(self.selectedDagNodes())
        self.propWidget.refresh()
        self.graphicsScene.refreshDrawNodes(nodesAffected)
When the user interface disconnects two nodes, tell the in-flight
dataset/ETHPy150Open andrew-gardner/dependsworkflow/depends/depends_main_window.py/MainWindow.nodesDisconnected