code: def onError(self, event):
      self.__errors += 1
      self.__checkStop()
  
imports: import unittest
  import threading
  import datetime
  from pyalgotrade.websocket import pusher
  from pyalgotrade.websocket import client
label_desc: Use image node_id 4 for calling the WebSocketClient obj's underlying member method code with example usage: obj.onError(event) without return types