input: Write a function to reverse the words in a string.
  assert reverseString("The quick brown fox.") == ['fox.', 'brown', 'quick', 'The']
  assert reverseString("hello world") == ['world', 'hello']
  assert reverseString("Python is awesome") == ['awesome', 'is', 'Python']
output: def reverseString(s):
      return s.split()[::-1]