input: def virtual_assistant_using_dialogflow() -> None:
      """ Create a virtual assistant using Python and Dialogflow to answer a basic set of questions.
      The assistant continuously prompts the user for input and responds using the Dialogflow API.
      Example:
      >>> virtual_assistant_using_dialogflow()
      User: What is the weather today?
      Assistant: The weather today is sunny with a high of 75°F.
      """
output:     import dialogflow
      import os
      from google.api_core.exceptions import InvalidArgument
  
      os.environ["GOOGLE_APPLICATION_CREDENTIALS"] = 'path_to_your_credentials_file.json'
  
      def detect_intent_texts(project_id, session_id, text, language_code):
          session_client = dialogflow.SessionsClient()
          session = session_client.session_path(project_id, session_id)
  
          text_input = dialogflow.types.TextInput(text=text, language_code=language_code)
          query_input = dialogflow.types.QueryInput(text=text_input)
  
          try:
              response = session_client.detect_intent(session=session, query_input=query_input)
          except InvalidArgument:
              raise
  
          return response.query_result.fulfillment_text
  
      project_id = 'your_project_id'
      session_id = 'unique_session_id'
      language_code = 'en'
  
      while True:
          user_input = input("User: ")
          if user_input.lower() in ['exit', 'quit']:
              break
          response = detect_intent_texts(project_id, session_id, user_input, language_code)
          print(f"Assistant: {response}")