old_contents: from beaker.middleware import SessionMiddleware
  from flask.sessions import SessionInterface
  
  
  class BeakerSessionInterface(SessionInterface):
      def open_session(self, app, request):
          if 'beaker.session' in request.environ:
              return request.environ['beaker.session']
          else:
              return {}
  
      def save_session(self, app, session, response):
          session.save()
  
  
  def configure(app, config):
  
      app.wsgi_app = SessionMiddleware(app.wsgi_app,
                                       {'session.type': config['session']['type'],
                                        'session.url': config['session']['url'],
                                        'session.data_dir': config['session']['data_dir']})
      app.session_interface = BeakerSessionInterface()
  
      return app
  
new_contents: from beaker.middleware import SessionMiddleware
  from flask.sessions import SessionInterface
  
  
  class BeakerSessionInterface(SessionInterface):
      def open_session(self, app, request):
          if 'beaker.session' in request.environ:
              return request.environ['beaker.session']
          else:
              return {}
  
      def save_session(self, app, session, response):
          session.save()
  
  
  def configure(app, config):
  
      app.wsgi_app = SessionMiddleware(
          app.wsgi_app,
          {'session.type': config['session']['type'],
           'session.url': config['session']['url'],
           'session.data_dir': config['session']['data_dir']})
      app.session_interface = BeakerSessionInterface()
  
      return app
  
subject: Fix flake8 issue.