input: Write a function to create a simple chatbot using Python and Dialogflow that can answer questions about the current days of the week. Implement the chatbot using Flask for handling HTTP requests and Dialogflow for processing the intents. If the session_id is not present in the request, create one before sending the text to Dialogflow for intent detection. 
  
  from flask import Flask
  from flask_restful import Resource, Api
  from dialogflow import detect_intent_texts
  
  app = Flask(__name__)
  api = Api(app)
  
  
  @app.route('/', methods=['GET', 'POST'])
  def detect_intent_text():
      IF session_id NOT present
          PLEASE create session_id
      request = detect_intent_texts(session_id, text)
      response = request.fulfillment_text
      return response
  
  
  if __name__ == '__main__':
      app.run()
  
  assert detect_intent_text("What day is it today?") == "Today is Monday."
  assert detect_intent_text("What day is it tomorrow?") == "Tomorrow is Tuesday."
  assert detect_intent_text("What was the day yesterday?") == "Yesterday was Sunday."
  assert detect_intent_text("") == ""
  assert detect_intent_text(None) == ""
output: 
  def detect_intent_text():
      from flask import request
      import uuid
      session_id = request.args.get('session_id')
      text = request.args.get('text')
      if not session_id:
          session_id = str(uuid.uuid4())
      request = detect_intent_texts(session_id, text)
      response = request.fulfillment_text
      return response
  