What does set do?

Answer 1

Sets are useful for removing multiples.
print(set([1, 2, 2, 4, 4, 4, 5]))
# output {1, 2, 4, 5}

Answer 2

A Set is an unordered collection data type that is iterable, mutable and has no duplicate elements. Python's setclass represents the mathematical notion of a set.

Answer 3

https://www.sololearn.com/learn/JUMP_LINK__&&__Python__&&__JUMP_LINK/2464/?ref=app