A Set is an unordered collection data type that is iterateable, mutable and has no duplicate elements. Python’s set class represents the mathematical notion of a set. The major advantage of using a set, as opposed to a list, is that it has a highly optimized method for checking whether a specific element is contained in the set.
Example:
# Python program to # demonstrate sets
# Same as {"a", "b", "c"}
myset = set(["a", "b", "c"])
print(myset)
# Adding element to the set
myset.add("d")
print(myset)
Output:
{'c', 'b', 'a'} {'d', 'c', 'b', 'a'}