I am the one with blind mask

As a lecturer i can also say that at this moment i discover that i don’t know any of the students names and i have to either refer to them as hey you, the guy at the back! or just get on with the lecture. Usually it’s the first one. All my students know i don’t know their names. But i can remember their work even years later. “Ahh it’s you.. the guy for whom urban utopia was entirely made of chocolate!”