old_contents: import falcon
  import json
  
  
  class SlackMessageRouter:
      def on_post(self, req, resp):
          resp.body = json.dumps({'message': 'hello, world!'})
          resp.status = falcon.HTTP_200
  
new_contents: import falcon
  import json
  
  
  class SlackMessageRouter:
      def on_post(self, req, resp):
          resp.body = json.dumps({'text': 'hello, world!'})
          resp.status = falcon.HTTP_200
  
subject: send slack-consumable response