class_docstr: A ZMQ socket invoking a callback in the ioloop
code: def close(self):
      if self.socket is not None:
          try:
              self.socket.close(linger=0)
          except Exception:
              pass
          self.socket = None
  
imports: from __future__ import absolute_import
  import atexit
  import errno
  import sys
  from threading import Thread, Event
  import time
  from zmq import ZMQError
  from zmq.eventloop import ioloop, zmqstream
  from traitlets import Type, Instance
  from jupyter_client.channels import HBChannel
  from jupyter_client import KernelClient
label_desc: Use image node_id 5 for calling the ThreadedZMQSocketChannel obj's underlying member method code with example usage: obj.close() without return types