And developer B inherits code from developer A who typed "import x", developer B curses and spends a few days implementing Y, which developer A should have done

And developer B inherits code from developer A who typed "import x", developer B curses and spends a few days implementing Y, which developer A should have done in the first place if he had listend to SO (and provided the context why he wanted to do X, which of course he didn't when asking the question).