code: def suite():
      isomorphism_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              IsomorphismTests
          )
      )
      subisomorphism_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              SubisomorphismTests
          )
      )
      permutation_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              PermutationTests
          )
      )
      automorphism_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              AutomorphismTests
          )
      )
      return unittest.TestSuite(
          [
              isomorphism_suite,
              subisomorphism_suite,
              permutation_suite,
              automorphism_suite,
          ]
      )
  
imports: import unittest
  from random import shuffle
  from igraph import Graph
label_desc: Use image node_id 3 for calling a global function with example usage: suite() and returns: unittest