Given a list of integers, return the difference between the largest and smallest integers in the list.
difference([10, 15, 20, 2, 10, 6]) ➞ 18
# 20 - 2 = 18
difference([-3, 4, -9, -1, -2, 15]) ➞ 24
# 15 - (-9) = 24
difference([4, 17, 12, 2, 10, 2]) ➞ 15
N/A