Comment by riobard

I'm not so sure if set notation is higher level, but for the example in your longer comment, map/filter/product is not that bad if you use it wisely. Here is my version:

    map(lambda (w,s,l): {'widget': w, 'sprocket': s, 'location': l}
        filter(lambda (w,s,l): l.hasInStock(w) and l.hasInStock(s) and w.isUsableWith(s), 
            product(widgets, sprockets, locations)))

Well, I agree it is not any conciser that its list comprehension (about the same I guess?). Nothing is perfect, like you said, know you tool :)