input: Write a function to determine if a given sentence is an 'affirmative' sentence or a 'negative' sentence. If the sentence contains any negation words, it should be classified as 'Negative'; otherwise, it should be classified as 'Affirmative'. If the sentence is empty, it should be considered 'Affirmative'.
  
  def isAffirmativeorNegative(sentence):
       negationwords = findNegation(sentence)
      if len(negationwords)==0: 
          return "Affirmative" 
      else: 
          return "Negative"  
  
  assert isAffirmativeorNegative("He always comes late but I dont mind.") == "Negative"
  assert isAffirmativeorNegative("She is very nice.") == "Affirmative"
  assert isAffirmativeorNegative("No one can help.") == "Negative"
  assert isAffirmativeorNegative("") == "Affirmative"
  assert isAffirmativeorNegative("This is not a test.") == "Negative"
output: def isAffirmativeorNegative(sentence):
      negationwords = ["no", "not", "never", "none", "nobody", "nothing", "neither", "nor"]
      words = sentence.lower().split()
      for word in words:
          if word in negationwords:
              return "Negative"
      return "Affirmative"