class_docstr: A simple displayhook that publishes the object's repr over a ZeroMQ
  socket.
class_docstr_tok: ["A","simple","displayhook","that","publishes","the","object","'s","repr","over","a","ZeroMQ","socket","."]
code: def __call__(self, obj):
      if obj is None:
          return
  
      builtin_mod._ = obj
      sys.stdout.flush()
      sys.stderr.flush()
      contents = {
          "execution_count": self.get_execution_count(),
          "data": {"text/plain": repr(obj)},
          "metadata": {},
      }
      self.session.send(
          self.pub_socket,
          "execute_result",
          contents,
          parent=self.parent_header,
          ident=self.topic,
      )
  
file_path: catboost/contrib/python/ipykernel/py2/ipykernel/displayhook.py
imports: import sys
  from IPython.core.displayhook import DisplayHook
  from ipykernel.jsonutil import encode_images, json_clean
  from ipython_genutils.py3compat import builtin_mod
  from traitlets import Instance, Dict, Any
  from jupyter_client.session import extract_header, Session
label_desc: Use image node_id 3 for calling the ZMQDisplayHook obj's underlying member method code with example usage: obj.__call__(obj) without return types