code: def preproc(path, sr=16000, alpha=0.95):
      
      oldsr, sig = wavfile.read(path)
  
      try:
          sig = sig[:, 0]
      except IndexError:
          pass
  
      if False and sr != oldsr:
          t = len(sig) / oldsr
          numsamp = int(t * sr)
          proc = resample(sig, numsamp)
      else:
          proc = sig
          sr = oldsr
      # proc = proc / 32768
      if alpha is not None and alpha != 0:
          proc = lfilter([1., -alpha], 1, proc)
      return sr, proc
docs: Preprocess a .wav file for later processing.  Currently assumes a
      16-bit PCM input.  Only returns left channel of stereo files.
  
      Parameters
      ----------
      path : str
          Full path to .wav file to load.
      sr : int, optional
          Sampling rate to resample at, if specified.
      alpha : float, optional
          Alpha for preemphasis, defaults to 0.97.
  
      Returns
      -------
      int
          Sampling rate.
      array
          Processed PCM.