input: Write a python function to calculate the difference between the maximum and minimum values in a list.
  assert maxMinDifference([3, 4, 7, 8, 12]) == 9
  assert maxMinDifference([15, 22, 1, 8, 19]) == 21
  assert maxMinDifference([-3, -7, -1, -5]) == 6
output: def maxMinDifference(lst):
      return max(lst) - min(lst)