Who's Johnny Testo

I met a guy yesterday who said his name was Johnny he said, 'they write songs about me, I know they do.' It came as quite a surprise in fact it opened my eyes and now I realize it's true. Johnny? Who's Johnny? and so I asked him hey Johnny where's your two bags and Jimmy and he just looked at me, funny you know like I was weird, I said now if it's really you, and if what you say is really true then you'd know what I'm saying? Just what am I saying? do you know what I'm saying?