input: Write a python function to swap positions in a list.
  assert swapPositions([4, 8, 1, 5], 0, 3) == [5, 8, 1, 4]
  assert swapPositions([1, 2, 3, 4, 5], 1, 4) == [1, 5, 3, 4, 2]
  assert swapPositions(['a', 'b', 'c', 'd'], 2, 3) == ['a', 'b', 'd', 'c']
output: def swapPositions(lst, pos1, pos2):
      lst[pos1], lst[pos2] = lst[pos2], lst[pos1]
      return lst