code: def setKeepAliveMgr(self, keepAliveMgr):
      if self.__keepAliveMgr is not None:
          raise Exception("KeepAliveMgr already set")
      self.__keepAliveMgr = keepAliveMgr
  
imports: import json
  import time
  import threading
  import six
  from ws4py.client import tornadoclient
  import tornado
  import pyalgotrade.logger
label_desc: Use image node_id 4 for calling the WebSocketClientBase obj's underlying member method code with example usage: obj.setKeepAliveMgr(keepAliveMgr) without return types