old_contents: import celery
  import os
  
  
  app = celery.Celery('rsvp')
  app.conf.update(BROKER_URL=os.environ['REDIS_URL'],
                  CELERY_RESULT_BACKEND=os.environ['REDIS_URL'])
  
  
  @app.task
  def add(x, y):
      return x + y
  
new_contents: import celery
  import os
  
  
  app = celery.Celery('tasks', broker=os.environ.get['REDIS_URL'], backend=os.environ.get['REDIS_URL'])
  
  
  @app.task
  def add(x, y):
      return x + y
  
subject: reconfigure celery app