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