input: Write a function to create a simple chatbot using Python and Dialogflow that can answer questions about the current days of the week. The function should handle requests via a Flask RESTful API and use Dialogflow's detect_intent_texts method to respond appropriately. If the session_id is not present, the function should create a session_id.
  
  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 today?', session_id='12345')=='Today is Monday.'
  assert detect_intent_text('What is the current day?', session_id='67890')=='The current day is Friday.'
  assert detect_intent_text('What is today?', session_id='11121')=='Today is Wednesday.'
output: 
  def detect_intent_text():
      if 'session_id' not in request.args:
          session_id = str(uuid.uuid4())
      else:
          session_id = request.args['session_id']
      text = request.args['text']
      request_result = detect_intent_texts(session_id, text)
      response = request_result.fulfillment_text
      return response
  