Sets in Python

Sets are another collection like lists and tuples that contain multiple values inside them with some differences: sets don't hold order and do not contain duplicate elements:

art_friends = {"Bob", "Anne"}
science_friends = {"Jen", "Charlie"}

Adding to a set:

art_friends.add("Jen")

Nothing happens if we do this again, because sets do not contain duplicates:

art_friends.add("Jen")

You can remove also:

art_friends.add("Anne")

Printing set will not keep initial order defined above.