input: Write a Python function to initialize a Dialogflow session and send a query.
  assert send_query('<my project id>', '<my session id>', 'Hello') is not None
  assert 'fulfillment_text' in send_query('<my project id>', '<my session id>', 'How are you?').keys()
  assert 'query_result' in send_query('<my project id>', '<my session id>', 'Tell me a joke').keys()
output: def send_query(project_id, session_id, query_text):
      from google.cloud import dialogflow_v2 as dialogflow
      import uuid
  
      session_client = dialogflow.SessionsClient()
      session = session_client.session_path(project_id, session_id or str(uuid.uuid4()))
  
      text_input = dialogflow.TextInput(text=query_text, language_code='en')
      query_input = dialogflow.QueryInput(text=text_input)
  
      response = session_client.detect_intent(request={"session": session, "query_input": query_input})
  
      return response.query_result