class_docstr: MessageTracker(*towatch)
  
  A class for tracking if 0MQ is done using one or more messages.
  
  When you send a 0MQ message, it is not sent immediately. The 0MQ IO thread
  sends the message at some later time. Often you want to know when 0MQ has
  actually sent the message though. This is complicated by the fact that
  a single 0MQ message can be sent multiple times using different sockets.
  This class allows you to track all of the 0MQ usages of a message.
  
  Parameters
  ----------
  towatch : Event, MessageTracker, Message instances.
      This objects to track. This class can track the low-level
      Events used by the Message class, other MessageTrackers or
      actual Messages.
docstr: Is 0MQ completely done with the message(s) being tracked?
docstr_tok: ["Is","0MQ","completely","done","with","the","message","(","s",")","being","tracked","?"]
code: def done(self):
      """Is 0MQ completely done with the message(s) being tracked?"""
      for evt in self.events:
          if not evt.is_set():
              return False
      for pm in self.peers:
          if not pm.done:
              return False
      return True
  
file_path: catboost/contrib/python/pyzmq/py3/zmq/sugar/tracker.py
imports: import time
  from threading import Event
  from typing import Set, Tuple, Union
  from zmq.backend import Frame
  from zmq.error import NotDone
label_desc: Use image node_id 2 for calling the MessageTracker obj's underlying member method code with example usage: obj.done() and returns: True, False, False