input: Write a python function to find the longest word in a list.
  assert findLongestWord(['Python', 'JavaScript', 'C++', 'Java', 'Kotlin']) == 'JavaScript'
  assert findLongestWord(['dog', 'elephant', 'cat']) == 'elephant'
  assert findLongestWord(['one', 'three', 'five', 'seven']) == 'three'
output: def findLongestWord(words):
      return max(words, key=len)