code: def fbank_feat(
      powspec,
      sr=8000,
      feature_size=40,
      nfft=512,
      lowfreq=0,
      highfreq=None,
  ):
      """return : [nframe, nfbank]"""
      feat = psf.logfbank_from_powspec(
          powspec,
          samplerate=sr,
          nfilt=feature_size,
          nfft=nfft,
          lowfreq=lowfreq,
          highfreq=highfreq,
      )
      return feat
  
file_path: delta/delta/data/feat/speech_feature.py
imports: import os
  import numpy
  import delta.compat
  from absl import logging
  from delta.data.feat import speech_ops
  from core.ops import py_x_ops
  from delta.data.feat import python_speech_features
label_desc: Use image node_id 9 for calling a global function with example usage: fbank_feat(powspec, sr, feature_size, nfft, lowfreq, highfreq) and returns: feat