code: def testChunkPageIds(self):
      results = scraper._chunk_page_ids(
          [1, 2, 3, 4, 5, 6, 7], chunk_size=3
      )
      self.assertSameElements(results, [[1, 2, 3], [4, 5, 6], [7]])
  
imports: from absl import flags
  from absl.testing import absltest
  from absl.testing import flagsaver
  import wikipedia_sourcelist_generator
label_desc: Use image node_id 1 for calling the WikipediaSourcelistGeneratorTests obj's underlying member method code with example usage: obj.testChunkPageIds() without return types