class_docstr: Create self-supervised control signal.
  
  EXPERIMENTAL
  
  Pass file_pattern to tfrecords created by `ddsp_generate_synthetic_data.py`.
class_docstr_tok: ["Create","self-supervised","control","signal",".","EXPERIMENTAL","Pass","file_pattern","to","tfrecords","created","by","`","ddsp_generate_synthetic_data.py","`","."]
code: def __init__(
      self,
      n_timesteps,
      n_harmonics,
      n_mags,
      file_pattern=None,
      sample_rate=16000,
  ):
      self.n_timesteps = n_timesteps
      self.n_harmonics = n_harmonics
      self.n_mags = n_mags
      super().__init__(
          file_pattern=file_pattern, sample_rate=sample_rate
      )
  
imports: import os
  from absl import logging
  from ddsp.spectral_ops import CREPE_FRAME_SIZE
  from ddsp.spectral_ops import CREPE_SAMPLE_RATE
  from ddsp.spectral_ops import get_framed_lengths
  import gin
  import tensorflow.compat.v2
  import tensorflow_datasets
label_desc: Use image node_id 1 to create a new SyntheticNotes object from inherited base classes: LegacyTFRecordProvider with example: obj = SyntheticNotes(n_timesteps, n_harmonics, n_mags, file_pattern, sample_rate)