code: def _send(self, req):
      # Since all the addresses were vetted, use the first one.
      addr = list(self._addresses.values())[0][0]
      return self._send_one(addr, req)
  
imports: import random
  import socket
  import struct
  import threading
  import cloudpickle
  import psutil
  from six.moves import queue, socketserver
  from bluefog.run.horovodrun.common.util import secret
label_desc: Use image node_id 5 for calling the BasicClient obj's underlying member method code with example usage: obj._send(req) and returns: self