input: from typing import NoReturn
  
  
  def run_virtual_assistant(project_id: str) -> NoReturn:
      """ Create a virtual assistant using Python and Dialogflow to answer basic questions.
      The assistant will continuously prompt the user for input and respond using Dialogflow's
      detect_intent method.
      >>> run_virtual_assistant('project-id')
      User: What's the weather today?
      Assistant: Light rain expected with a high of 55°F and a low of 43°F.
      User: Thank you!
      Assistant: You're welcome!
      """
      import dialogflow_v2 as dialogflow
  
      session_client = dialogflow.SessionsClient()
      session = session_client.session_path(project_id, 'session-id')
  
      while True:
          text = input('User: ')
          text_input = dialogflow.types.TextInput(text=text, language_code='en-US')
          query_input = dialogflow.types.QueryInput(text=text_input)
          response = session_client.detect_intent(session=session, query_input=query_input)
  
          print('Assistant:', response.query_result.fulfillment_text)
output:     if response.query_result.intent.is_fallback:
          print('Assistant: I didn\'t understand that. Could you please rephrase?')