input: from typing import List
  
  def reverse_words(str: str) -> str:
      """ Reverse the order of words in a given string.
      >>> reverse_words("Hello World")
      'World Hello'
      >>> reverse_words("Python Programming is fun")
      'fun is Programming Python'
      """
output:     words = str.split()
      reversed_words = words[::-1]
      return ' '.join(reversed_words)