code: def _istft(y, hparams):
      return librosa.istft(
          y,
          hop_length=get_hop_size(hparams),
          win_length=hparams["win_size"],
      )
  
file_path: PaddleHub/modules/audio/svs/diffsinger/utils/audio.py
imports: import subprocess
  import matplotlib
  import librosa
  import librosa.filters
  import numpy
  from scipy import signal
  from scipy.io import wavfile
label_desc: Use image node_id 4 for calling a global function with example usage: _istft(y, hparams) and returns: librosa