class_docstr: Expand delta-deltas features from spectrum.
code: def from_config_dict(cls, config=None):
      _config = {} if config is None else config
      return DeltaDeltas(_config.get("win_length", 5))
  
file_path: fairseq/fairseq/data/audio/feature_transforms/delta_deltas.py
imports: import numpy
  import torch
  from fairseq.data.audio.feature_transforms import AudioFeatureTransform, register_audio_feature_transform
label_desc: Use image node_id 1 for calling the DeltaDeltas obj's underlying member method code with example usage: obj.from_config_dict(cls, config) and returns: DeltaDeltas