code: def test_remove_duplicate_text(self):
      import apache_beam.testing.util as beam_testing_util  # pylint:disable=g-import-not-at-top
  
      beam = lazy_imports.apache_beam
      input_pages = [
          PageFeatures(
              url="url/1-0",
              text="This is a duplicated line.\nThis is a unique line.\n"
              + "This one comes first and so it stays.\n"
              + "This is duplicate within the page so the others are removed.\n"
              + "Here is a sentence between the duplicates.\n"
              + "This is duplicate within the page so the others are removed.\n"
              + "this is Duplicate WITHIN the page so the others are removed. ",
          ),
          PageFeatures(
              url="url/2-1",
              text="This is 2nd unique line.\nThis one comes second so it is "
              + "removed even though the capitalizaiton is different.\n"
              + "this is a Duplicated line. ",
          ),
          PageFeatures(
              url="url/3-4",
              text="This is a 3rd unique line.\nThis is a duplicated line.\n"
              + "This one comes third and so it is removed. But the page stays "
              + "because there are still 3 sentences remaining.",
          ),
          PageFeatures(
              url="url/4-4",
              text="This is a 4th unique line.\nThis is a duplicated line.\n"
              + "This one comes third and so it is removed, and the page is too "
              + "since there aren't enough sentences left.",
          ),
      ]
      expected_pages = [
          PageFeatures(
              url="url/1-0",
              text="This is a duplicated line.\nThis is a unique line.\n"
              + "This one comes first and so it stays.\n"
              + "This is duplicate within the page so the others are removed.\n"
              + "Here is a sentence between the duplicates.",
          ),
          PageFeatures(
              url="url/3-4",
              text="This is a 3rd unique line.\n"
              + "This one comes third and so it is removed. But the page stays "
              + "because there are still 3 sentences remaining.",
          ),
      ]
      with beam.Pipeline() as pipeline:
          pages = pipeline | beam.Create(input_pages)
          deduped_pages = c4_utils.remove_duplicate_text(pages)
          beam_testing_util.assert_that(
              deduped_pages, beam_testing_util.equal_to(expected_pages)
          )
  
imports: import collections
  import os
  import six
  from tensorflow_datasets import testing
  from tensorflow_datasets.core.lazy_imports_lib import lazy_imports
  from tensorflow_datasets.text import c4_utils
label_desc: Use image node_id 8 for calling the C4UtilsTest obj's underlying member method code with example usage: obj.test_remove_duplicate_text() without return types