auto flex_builder = std::make_unique<flexbuffers::Builder>();
        size_t map_start = flex_builder->StartMap();
        auto attrs = vhlo_op->getAttrs();
        std::vector<mlir::NamedAttribute> extra_attributes;

        for (size_t i = 0; i < attrs.size(); ++i) {
          auto name = attrs[i].getName().str();
          auto attr = attrs[i].getValue();