Understanding the set() function

Question

In python, set() is an unordered collection with no duplicate elements. However, I am not able to understand how it generates the output.

For example,

Answer 1

After reading the other answers, I still had trouble understanding why the set comes out un-ordered.

Mentioned this to my partner and he came up with this metaphor: take marbles. You put them in a tube a tad wider than marble width : you have a list. A set, however, is a bag. Even though you feed the marbles one-by-one into the bag; when you pour them from a bag back into the tube, they will not be in the same order (because they got all mixed up in a bag).