Many patients misunderstand what therapy reliably provides.

The bags were developed as an alternative to paper bags, which were considered bad for the environment because they resulted in forests being chopped down.

They were significantly stronger than paper bags, which meant – in theory – they could be used over and over again.

However, single-use plastic took off and now our consumption of this polluting material is one of the biggest threats facing the world’s seas, with marine plastic set to outweigh fish by 2050.

Raoul Thulin, son of Sten, told the BBC: “To my dad, the idea that people would simply throw these away would be bizarre. He always carried [a plastic bag] in his pocket folded up. You know what we’re all being encouraged to do today, which is to take your bags back to the shop, he was doing back in the Seventies and Eighties, just naturally, because, well, why wouldn’t you?”

A description of some of the recent changes to do allocations on the stack instead of the heap.