I think that whatever form of notation that you choose to use, you should stick with. If you use parentheses with open() or not, or if you like spacing a certain way, or if you indent a certain way, be consistent
. I know that in order to keep my own mental space clear of confusion, I really need to do thing the same way every time, in my own style. If I do not, I start to wonder why I did something differently in one place than I did in another when I am trying to accomplish the same thing.