code: def __init__(self, *args, **kwargs):
      super().__init__(*args, **kwargs)
      self._ping_callback = ioloop.PeriodicCallback(
          self._callback,
          callback_time=self._interval,
      )
  
file_path: perspective/python/perspective/perspective/client/tornado.py
imports: from tornado import ioloop
  from tornado.websocket import websocket_connect
  from .websocket import PerspectiveWebsocketClient, PerspectiveWebsocketConnection, Periodic
label_desc: Use image node_id 1 to create a new TornadoPeriodic object from inherited base classes: Periodic with example: obj = TornadoPeriodic()