input: Write a python function to find the longest word(s) in a list of words.
  assert longest_word(["Hello", "World", "Welcome", "To", "the", "universe"]) == ["Welcome", "universe"]
  assert longest_word(["apple", "banana", "pear", "kiwi", "strawberry"]) == ["strawberry"]
  assert longest_word(["short", "longer", "longest"]) == ["longest"]
output: def longest_word(words):
      max_length = max(len(word) for word in words)
      return [word for word in words if len(word) == max_length]