Of all the professions regularly committed to celluloid, some are more common than others. Journalist, say. Lawyer. Professor at a university. You rarely see films about binmen or sewage workers, yet someone has that job. Novelist is for some reason also a common trope. Since becoming one myself, I can barely sit through a film without shouting ‘It’s not like that! They’d never be able to afford that car! Their editor would never pick them up from the airport!’ and so on, while weeping bitter tears into the popcorn I had to bring from home, and then struggling to see from under the seat I had to sneak into wearing a large coat and standing on my friend’s shoulders (oh, you see where I’m going with this: being a writer doesn’t pay all that well). Having watched a raft of films over Christmas which featured writers in central roles, I…