text: #include <tuple>
  
  template<size_t I, size_t J, class...Args>
  auto to_pair(const std::tuple<Args...> t) -> decltype(std::make_pair(std::get<I>(t), std::get<J>(t))) {
      return std::make_pair(std::get<I>(t), std::get<J>(t));
  };