input: from collections import Counter
  
  def frequent_words(words: Counter, n: int) -> list:
      """Takes a list of words and an integer n and returns a list of words that appear at least n times in the given list.
      >>> frequent_words(['a', 'b', 'a', 'c', 'd', 'a', 'x', 'd', 'd'], 3)
      ['a', 'd']
      """
output:     return [word for word, count in words.items() if count >= n]