input: 
  def get_virtual_assistant_response() -> str:
      """ Implement a virtual assistant using DialogFlow and Python that takes user input
      and returns the assistant's response. The session ID should be fixed as 'session-id'.
  
      >>> get_virtual_assistant_response()
      'User: Hello\\nAssistant: Hi how can I help you?'
      """
  
output:     
      import dialogflow_v2 as dialogflow
      from google.protobuf.json_format import MessageToJson
  
      def detect_intent_texts(project_id, session_id, texts, language_code):
          session_client = dialogflow.SessionsClient()
          session = session_client.session_path(project_id, session_id)
  
          for text in texts:
              text_input = dialogflow.types.TextInput(text=text, language_code=language_code)
              query_input = dialogflow.types.QueryInput(text=text_input)
              response = session_client.detect_intent(session=session, query_input=query_input)
              return response.query_result.fulfillment_text
  
      def get_virtual_assistant_response() -> str:
          project_id = 'your-project-id'
          session_id = 'session-id'
          user_input = 'Hello'
          language_code = 'en'
  
          assistant_response = detect_intent_texts(project_id, session_id, [user_input], language_code)
          return f'User: {user_input}\nAssistant: {assistant_response}'
  