input: Write a function to determine if a given sentence is an 'affirmative' sentence or a 'negative' sentence. If the sentence contains no negation words, it is considered 'affirmative'; otherwise, it is considered 'negative'. The function should return the string "Affirmative" or "Negative" based on the presence of negation words.
  assert isAffirmativeorNegative("He always comes late but I dont mind.") == "Negative"
  assert isAffirmativeorNegative("She loves to read books.") == "Affirmative"
  assert isAffirmativeorNegative("No one was at the meeting.") == "Negative"
  assert isAffirmativeorNegative("We had a great time.") == "Affirmative"
output: def isAffirmativeorNegative(sentence):
      negation_words = {"no", "not", "never", "none", "nobody", "nothing", "neither", "nor"}
      words = sentence.lower().split()
      for word in words:
          if word in negation_words:
              return "Negative"
      return "Affirmative"