How many numbers would be printed?

Question

a = {1, 2, 3, 4, 5, 6}
b = {4, 5, 6, 7, 8, 9}
print(a^b)

Answer is 6

Answer 1

You do symmetric difference operation on two sets.
Its result is new set with elements which exist in either 1st set or 2nd set but not both

1, 2, 3 are only in 1st set
4, 5, 6 are in both sets.
7, 8, 9 are only in 2nd set

so result will be {1, 2, 3, 7, 8, 9} - 6 numbers