code: def _create_stream(self, max_buffer_size, af, addr, **kwargs):  # pylint: disable=unused-argument
          '''
          Override _create_stream() in TCPClient.
  
          Tornado 4.5 added the kwargs 'source_ip' and 'source_port'.
          Due to this, use **kwargs to swallow these and any future
          kwargs to maintain compatibility.
          '''
          # Always connect in plaintext; we'll convert to ssl if necessary
          # after one connection has completed.
          sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
          _set_tcp_keepalive(sock, self.opts)
          stream = tornado.iostream.IOStream(
              sock,
              max_buffer_size=max_buffer_size)
          if tornado.version_info < (5,):
              return stream.connect(addr)
          return stream, stream.connect(addrf _create_stream(self, max_buffer_size, af, addr, **kwargs):  # pylint: disable=unused-argument
          '''
          Override _create_stream() in TCPClient.
  
          Tornado 4.5 added the kwargs 'source_ip' and 'source_port'.
          Due to this, use **kwargs to swallow these and any future
          kwargs to maintain compatibility.
          '''
          # Always connect in plaintext; we'll convert to ssl if necessary
          # after one connection has completed.
          sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
          _set_tcp_keepalive(sock, self.opts)
          stream = tornado.iostream.IOStream(
              sock,
              max_buffer_size=max_buffer_size)
          if tornado.version_info < (5,):
              return stream.connect(addr)
          return stream, stream.connect(addr)
docs: Override _create_stream() in TCPClient.
  
          Tornado 4.5 added the kwargs 'source_ip' and 'source_port'.
          Due to this, use **kwargs to swallow these and any future
          kwargs to maintain compatibility.