Status GetFunctionNameAttr(Node const* node, string* attr) const;

  // Copies edges local to a subgraph. Adds _Arg and _Retval nodes to
  // subgraphs for data edges that cross subgraph boundaries.
  Status CopySubgraphEdges(
      const absl::flat_hash_map<const Node*, Node*>& node_images,
      std::vector<std::pair<const Node*, Node*>>* src_arg_pairs);

  // Copies all marked nodes to a subgraph. Does nothing for unmarked nodes.