code: def test_comparing_empty_lists(self):
      # Check fix for bug #979794
      group_gen = difflib.SequenceMatcher(
          None, [], []
      ).get_grouped_opcodes()
      self.assertRaises(StopIteration, next, group_gen)
      diff_gen = difflib.unified_diff([], [])
      self.assertRaises(StopIteration, next, diff_gen)
  
imports: import difflib
  from test.support import findfile
  import unittest
  import doctest
  import sys
label_desc: Use image node_id 2 for calling the TestSFbugs obj's underlying member method code with example usage: obj.test_comparing_empty_lists() without return types