input: Write a python function to find the union of two lists.
  assert findUnion([1, 2, 3, 4], [6, 5, 4, 3]) == [1, 2, 3, 4, 6, 5]
  assert findUnion([1, 2], [3, 4]) == [1, 2, 3, 4]
  assert findUnion([1, 1, 1], [2, 2, 2]) == [1, 2]
output: def findUnion(list1, list2):
      return list(set(list1) | set(list2))