code: def _build_dataset(self, num_epochs, compression_type=None):
      filenames = self._createFiles()
      return readers.FixedLengthRecordDataset(
          filenames,
          self._record_bytes,
          self._header_bytes,
          self._footer_bytes,
      ).repeat(num_epochs)
  
imports: import gzip
  import os
  import pathlib
  import zlib
  from absl.testing import parameterized
  from tensorflow.python.data.kernel_tests import checkpoint_test_base
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import readers
  from tensorflow.python.framework import combinations
  from tensorflow.python.framework import errors
  from tensorflow.python.platform import test
  from tensorflow.python.util import compat
label_desc: Use image node_id 1 for calling the FixedLengthRecordDatasetCheckpointTest obj's underlying member method code with example usage: obj._build_dataset(num_epochs, compression_type) and returns: readers