I thank you for this example. If the operator definitions are not trivial and you want to keep them well mantained, then your example is very good.
However, what I meant was that for fast, quick coding, if your 'operator' function is really simple, then lambda fints perfectlu.
I know the Zen of Python says: "There should be one—and preferably only one—obvious way to do it", but i don't align to that principle. I think there should be more than one way to do something, and one should choose one that fits the best.