40C is common over there in the summer even in the south where I'm from, but we build for it, so almost everyone from low middle class up has venetian blinds (lets the air in keeping the sun out) and air-gapped double walls. Airco used to be a rich people thing until fifteen years ago or such, but it's much more common now, especially in apartments. I went through most of my life there without it and remember only one summer of real discomfort for a few days.

Also the country basically stops from Christmas to Carnaval, and forty degrees is not as bad if you're drinking ice-cold beer at the beach or by the pool, tbh.