return "";
  }
  return std::string(entry->second);
}

string WriteClassFuzzDef(const OpInfo& op_info) {
  string class_signature_str = absl::Substitute(
      "class Fuzz$0 : public FuzzSession<$1> {\n", op_info.op_name,
      absl::StrJoin(op_info.graph_op_def.input_arg(), ", ",
                    [](string* out, const auto arg) {
                      strings::StrAppend(out, "Tensor");