Are Python sets mutable

Question

In other words, if I do this:

x = set([4, 5, 6])
y = x

y |= set([7, 8, 9])

Are x and y still pointing to the same object, or was a new set created and assigned to y?

Answer 1

>>>> x = set([4, 5, 6])

• Sets are unordered.

• Set elements are unique.

• It is not permitted to use duplicate elements.

• A set's elements can be changed, but the set's elements must be of an immutable type.

set1 = {4,5,6}

set2 = {4,5,[4,5]}  --> unhashable type: 'list'
# Set elements should be immutable.

Hence, we can see that sets are mutable.