input: Write a function to order words by their length in descending order.
  assert order_by_length(["Hello", "World", "This", "is", "a", "test"]) == ["Hello", "World", "This", "test", "is", "a"]
  assert order_by_length(["Python", "is", "awesome"]) == ["awesome", "Python", "is"]
  assert order_by_length(["short", "tiny", "medium", "longer", "longest"]) == ["longest", "medium", "longer", "short", "tiny"]
output: def order_by_length(words):
      return sorted(words, key=len, reverse=True)