input: Write a function to count unique elements in a list.
  assert uniqueCount([10, 12, 10, 4, 10, 6, 4]) == 4
  assert uniqueCount([1, 2, 3, 4, 5]) == 5
  assert uniqueCount([5, 5, 5, 5, 5]) == 1
output: def uniqueCount(lst):
      return len(set(lst))