docstr: Returns the IP address of the current node.
code: def get_node_ip(self):
      """Returns the IP address of the current node."""
      return ray._private.services.get_node_ip_address()
  
imports: import time
  import argparse
  import tensorflow
  import os
  import sys
  import math
  import collections
  from tensorflow.python.client import timeline
  import json
  from tensorflow.python.ops import partitioned_variables
  import ray
  from bigdl.dllib.utils.log4Error import *
  from bigdl.orca import init_orca_context, stop_orca_context, OrcaContext
  from bigdl.orca.data.utils import process_spark_xshards
  from bigdl.orca.learn.utils import maybe_dataframe_to_xshards
  from bigdl.friesian.feature import FeatureTable
label_desc: Use image node_id 9 for calling the RayWorker obj's underlying member method code with example usage: obj.get_node_ip() and returns: ray