input: def generate_response(question: str) -> str:
      """ Generate a response to a user's question about a product or service. The function uses a predefined list of answers for known queries. If the question is not in the list, it returns a random response indicating uncertainty.
      >>> generate_response('What is XYZ?')
      'XYZ is a company that provides XYZ services.'
      >>> generate_response('Where is XYZ located?')
      'XYZ is located in ABC city.'
      >>> generate_response('How does XYZ work?')
      'I am not sure I understand.'
      """
output:     predefined_answers = {
          'What is XYZ?': 'XYZ is a company that provides XYZ services.',
          'Where is XYZ located?': 'XYZ is located in ABC city.',
          'How does XYZ work?': 'XYZ works by following a specific process.'
      }
      
      return predefined_answers.get(question, 'I am not sure I understand.')