code: def test_find_maximal_cliques_2x2(self):
      adj_matrix = DataFrame(
          [[0, 1], [1, 0]],
          columns=["a", "b"],
          index=["a", "b"],
      )
      expected = [{"a", "b"}]
      self.assertEqual(splt._find_maximal_cliques(adj_matrix), expected)
  
imports: import os
  import sys
  import unittest
  import matplotlib
  import scikit_posthocs._posthocs
  import scikit_posthocs._omnibus
  import scikit_posthocs._outliers
  import scikit_posthocs._plotting
  import scikit_posthocs._global
  import seaborn
  import numpy
  import matplotlib.axes
  from pandas import DataFrame, Series
label_desc: Use image node_id 9 for calling the TestPosthocs obj's underlying member method code with example usage: obj.test_find_maximal_cliques_2x2() without return types