const absl::string_view src_saved_model_path,
      const std::unordered_set<std::string>& tags,
      const absl::flat_hash_map<std::string, SignatureDef>& signature_def_map)
      const override {
    PYBIND11_OVERRIDE_PURE(std::optional<bool>, PyFunctionLibrary,
                           save_exported_model, dst_saved_model_path,
                           exported_model, src_saved_model_path, tags,