absl::StatusOr<uint64_t> RegularizeAndHashSavedObjectGraph(
    const SavedObjectGraph& object_graph_def) {
  // Sort `concrete_functions`, which is an unordered map from function names to
  // SavedConcreteFunction, using the suffix UID of the function name. Assumes
  // that the trackable children are listed in a deterministic order during
  // serialization.
  absl::btree_map<int64_t, std::string> uid_to_function_names;

      // We only allow a single input signature to each SavedFunction.
      // This assumption means we have a 1:1 correspondence between
      // tf.function <=> SavedFunction <=> SavedConcreteFunction <=> FunctionDef
      // This makes defining the ABI easier (or even well-defined at all).
      // TODO(silvasean): How to detect a function that doesn't have an