input: Write a python function to classify a film review as either Positive or Negative.
  assert classify_review('The film was so captivating! Absolutely loved it!') == 'Positive'
  assert classify_review('It was a waste of time, not worth watching.') == 'Negative'
  assert classify_review('An average movie, nothing special.') == 'Negative'
  assert classify_review('Absolutely fantastic! Brilliant performances!') == 'Positive'
output: def classify_review(review):
      positive_keywords = ['captivating', 'loved', 'fantastic', 'brilliant']
      negative_keywords = ['waste of time', 'not worth', 'average', 'nothing special']
      
      review_lower = review.lower()
      
      if any(keyword in review_lower for keyword in positive_keywords):
          return 'Positive'
      
      if any(keyword in review_lower for keyword in negative_keywords):
          return 'Negative'
      
      return 'Negative'