class_docstr: AliasSampleTest
      
code: def setUp(self):
      pass
  
file_path: PGL/legacy/pgl/tests/deepwalk/test_alias_sample.py
imports: import argparse
  import time
  import unittest
  from collections import Counter
  import numpy
  from pgl.graph_kernel import alias_sample_build_table
  from pgl.sample import alias_sample
label_desc: Use image node_id 1 for calling the AliasSampleTest obj's underlying member method code with example usage: obj.setUp() without return types