code: def test_centering(self, center):
      frame_rate = 250
      sample_rate = 16000
      example_secs = 0.3
      hop_secs = 0.1
      n_batch = self.get_n_per_chunk(
          self.wav_secs, example_secs, hop_secs
      )
      prepare_tfrecord_lib.prepare_tfrecord(
          [self.wav_path],
          os.path.join(self.test_dir, "output.tfrecord"),
          num_shards=2,
          sample_rate=sample_rate,
          frame_rate=frame_rate,
          example_secs=example_secs,
          hop_secs=hop_secs,
          center=center,
          chunk_secs=None,
      )
  
      n_t = int(example_secs * sample_rate)
      n_frames = self.get_expected_length(n_t, frame_rate, center)
      n_expected_frames = 76 if center else 75  # (250 * 0.3) [+1].
      self.assertEqual(n_frames, n_expected_frames)
      self.validate_outputs(
          n_batch,
          {
              "audio": n_t,
              "audio_16k": n_t,
              "f0_hz": n_frames,
              "f0_confidence": n_frames,
              "loudness_db": n_frames,
          },
      )
  
imports: import os
  import sys
  from absl import flags
  from absl.testing import absltest
  from absl.testing import parameterized
  from ddsp import spectral_ops
  from ddsp.training.data_preparation import prepare_tfrecord_lib
  import numpy
  import scipy.io.wavfile
  import tensorflow.compat.v2
label_desc: Use image node_id 8 for calling the PrepareTFRecordBeamTest obj's underlying member method code with example usage: obj.test_centering(center) without return types