code: def GetRouterForUser(self, username):
      
  
      for index, router in enumerate(self.routers):
        router_id = str(index)
  
        if self.auth_manager.CheckPermissions(username, router_id):
          logging.debug("Matched router %s to user %s", router.__class__.__name__,
                        username)
          return router
  
      logging.debug("No router ACL rule match for user %s. Using default "
                    "router %s", username, self.default_router.__class__.__name__)
      return self.default_router
docs: Returns a router corresponding to a given username.