input: Write a function to reverse the words in a string.
  assert reverseWords("This is an example sentence.") == "sentence. example an is This"
  assert reverseWords("Hello world") == "world Hello"
  assert reverseWords("The quick brown fox") == "fox brown quick The"
output: def reverseWords(s: str) -> str:
      return ' '.join(s.split()[::-1])