input: Write a function to determine if a given sentence is an 'affirmative' sentence or a 'negative' sentence. If the sentence contains negation words, return "Negative" otherwise return "Affirmative". If the input sentence is empty, return "Affirmative".
  
  assert isAffirmativeorNegative("He always comes late but I dont mind.") == "Negative"
  assert isAffirmativeorNegative("She is going to the park.") == "Affirmative"
  assert isAffirmativeorNegative("I cannot attend the meeting.") == "Negative"
  assert isAffirmativeorNegative("") == "Affirmative"
output: def isAffirmativeorNegative(sentence):
      negation_words = ["not", "no", "never", "none", "nobody", "nothing", "nowhere", "neither", "nor", "cannot"]
      if not sentence:
          return "Affirmative"
      for word in negation_words:
          if word in sentence.lower():
              return "Negative"
      return "Affirmative"