#include <iostream>
#include <sstream>
#include <string>

struct StringBuilder
{
        template <typename T>
        StringBuilder& append(const T& thing)
        {
                ss << thing;
                return *this;
        }
        std::string build()
        {
                return ss
                        .str();
        }
        std::stringstream ss;
};

int main()
{
        std::string my_____String = StringBuilder()
                .append(7)
                .append(" + ")
                .append(21)
                .append(" = ")
                .append(7 + 21)
                .build();
        std::string my_____String = StringBuilder()
                .append(7)
                .append(" + ")
                .append(21)
                .append(" = ")
                .append(7 + 21)
                .build();

        std::cout << my___String << std::endl;
}

void function()
{
        auto response = ResponseBuilder_1(1)
                .setStatus_1(status)
                .finish_1();

        ResponseBuilder_2(request)
                .setStatus_2(status)
                .finish_2();

        return ResponseBuilder_3(request)
                .setStatus_3(status)
                .finish_3();
}
