class_docstr: A large-scale and high-quality dataset of annotated musical notes.
code: def _info(self):
      features = {
          "id": tf.string,
          "audio": tfds.features.Audio(
              shape=(_AUDIO_RATE * _NUM_SECS,),
              dtype=np.float32,
              sample_rate=_AUDIO_RATE,
          ),
          "pitch": tfds.features.ClassLabel(num_classes=128),
          "velocity": tfds.features.ClassLabel(num_classes=128),
          "instrument": {
              # We read the list of labels in _split_generators.
              "label": tfds.features.ClassLabel(num_classes=1006),
              "family": tfds.features.ClassLabel(
                  names=_INSTRUMENT_FAMILIES
              ),
              "source": tfds.features.ClassLabel(
                  names=_INSTRUMENT_SOURCES
              ),
          },
          "qualities": {quality: tf.bool for quality in _QUALITIES},
      }
      if self.builder_config.estimate_f0_and_loudness:
          f0_and_ld_shape = (_F0_AND_LOUDNESS_RATE * _NUM_SECS,)
          features["f0"] = {
              "hz": tfds.features.Tensor(
                  shape=f0_and_ld_shape, dtype=np.float32
              ),
              "midi": tfds.features.Tensor(
                  shape=f0_and_ld_shape, dtype=np.float32
              ),
              "confidence": tfds.features.Tensor(
                  shape=f0_and_ld_shape, dtype=np.float32
              ),
          }
          features["loudness"] = {
              "db": tfds.features.Tensor(
                  shape=f0_and_ld_shape, dtype=np.float32
              )
          }
      return self.dataset_info_from_configs(
          features=tfds.features.FeaturesDict(features),
          homepage="https://g.co/magenta/nsynth-dataset",
          metadata=tfds.core.BeamMetadataDict(
              sample_rate=_AUDIO_RATE,
          ),
      )
  
file_path: datasets/tensorflow_datasets/datasets/nsynth/nsynth_dataset_builder.py
imports: from __future__ import annotations
  import csv
  import os
  import numpy
  from tensorflow_datasets.core.utils.lazy_imports_utils import tensorflow
  import tensorflow_datasets.public_api
label_desc: Use image node_id 1 for calling the Builder obj's underlying member method code with example usage: obj._info() and returns: self