[dosisod]

You're right! I guess you can't rely on sets being iterated over in order (not that you ever should rely on that). Moreover I was trying to show that you can use lists, tuples, and sets as temporary iterable objects, though but no-one (that I have seen) uses sets in that way.

[yunohn]

Sets are more useful when you want to dedupe unknown data. Defining a set with constants to use immediately in a for loop is not very helpful compared to a tuple or a list.

Also, you can make anything iterable in python if you implement __iter__.