code: def suite():
      direction_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              DirectedUndirectedTests
          )
      )
      representation_suite = (
          unittest.defaultTestLoader.loadTestsFromTestCase(
              GraphRepresentationTests
          )
      )
      return unittest.TestSuite([direction_suite, representation_suite])
  
file_path: python-igraph/tests/test_conversion.py
imports: import random
  import unittest
  from igraph import Graph, Matrix
label_desc: Use image node_id 1 for calling a global function with example usage: suite() and returns: unittest