code: def download_data(self, source_url, out_dir):
      fb_tgz_dir = os.path.join(out_dir, "wn18.tgz")
      DataSet.download_file(self.source_url, fb_tgz_dir)
      with tarfile.open(fb_tgz_dir) as fb_file:
          print("unzip data..")
          fb_file.extractall(out_dir)
  
file_path: euler/tf_euler/python/dataset/wn18.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import json
  import urllib
  import tarfile
  import tqdm
  from tf_euler.python.dataset.sage_util import *
  from tf_euler.python.dataset.base_dataset import DataSet
label_desc: Use image node_id 2 for calling the WN18 obj's underlying member method code with example usage: obj.download_data(source_url, out_dir) without return types