// - Replacing LegacyFedInput nodes with Placeholder nodes if
//   convert_legacy_fed_inputs option is enabled.
Status PreprocessGraphDef(const GraphImportConfig* specs, GraphDef* graph_def) {
  for (auto& node_def : *graph_def->mutable_node()) {
    // TODO(hinsu): Completely deprecate support for LegacyFedInput ops. One
    // solution could be have a tool to let users upgrade old serialized graphs.
    if (specs && specs->convert_legacy_fed_inputs &&

      result.Append(std::move(pad));
    }
    AppendBufferData(result);
    std::string result_str = std::string(std::move(result));
    auto mutable_model = tflite::GetMutableModel(result_str.data());
    bool ret = UpdateBufferOffsets(mutable_model);
    if (!ret) {
      return std::nullopt;
    }
    return result_str;
  }
  return std::string(result);
}