input: def generate_natural_language_response(utterance: str) -> str:
      """Generate a natural language response to a given utterance using a trained model.
      >>> generate_natural_language_response("What time is it?")
      'The time is 3:45 PM'
      """
output:     from transformers import pipeline
      generator = pipeline('text-generation')
      response = generator(utterance, max_length=50)
      return response[0]['generated_text']