step_tree.py 文件源码

def to_pydot(self):
        """Return a pydot digraph from a StepTree."""

        graph = pydot.Dot(graph_type='digraph')

        # make sure Root shows up in single node trees
        if self.root_name:
            graph.add_node(pydot.Node(self._step_graph_label(self.root_name)))

        for parent, children in self.children.items():
            for child in children:
                graph.add_edge(pydot.Edge(
                    self._step_graph_label(parent),
                    self._step_graph_label(child)
                    ))

        return graph