code: def testClusteringIndex(self):
      self.assertTrue(self.cl[0] == [0, 1, 2])
      self.assertTrue(self.cl[1] == [3, 4, 6, 7])
      self.assertTrue(self.cl[2] == [5])
      self.assertTrue(self.cl[3] == [])
      self.assertTrue(self.cl[4] == [8, 9])
  
imports: import math
  import random
  import unittest
  from igraph import Clustering, CohesiveBlocks, Cover, Graph, Histogram, InternalError, UniqueIdGenerator, VertexClustering, compare_communities, split_join_distance, set_random_number_generator
label_desc: Use image node_id 2 for calling the ClusteringTests obj's underlying member method code with example usage: obj.testClusteringIndex() without return types