def reserve_app_id(self, username, app_id, app_language):
    result = self.server.commit_new_app(app_id, username, app_language,
      self.secret)
    if result == "true":
      AppScaleLogger.log("We have reserved {0} for your app".format(app_id))
    elif result == "Error: appname already exist":
      AppScaleLogger.log("We are uploading a new version of your app.")
    elif result == "Error: User not found":
      raise AppScaleException("No information found about user {0}" \
        .format(username))
    else:
      raise AppScaleException(result)
Internally indicates that a node has been removed from the ISY.
dataset/ETHPy150Open AppScale/appscale-tools/lib/user_app_client.py/UserAppClient.reserve_app_id--crossover with--dataset/ETHPy150Open UniversalDevicesInc/Polyglot/polyglot/nodeserver_api.py/SimpleNodeServer.on_removed