input: 
  def classify_text_sentiment(text: str, classifier) -> str:
      """ Classify a given text document into two classes: positive or negative, using a pre-trained NaiveBayesClassifier.
      >>> classify_text_sentiment("This is a great movie!", classifier)
      'positive'
      >>> classify_text_sentiment("This movie was terrible", classifier)
      'negative'
      >>> classify_text_sentiment("This movie was ok", classifier)
      'positive'
      """
  
output:     sentiment = classifier.classify(text)
      return sentiment