code: def _stft(self, y):
      return librosa.stft(
          y=y,
          n_fft=self.fft_size,
          hop_length=self.hop_length,
          win_length=self.win_length,
          pad_mode=self.stft_pad_mode,
      )
  
imports: import librosa
  import soundfile
  import numpy
  import scipy.io.wavfile
  import scipy.signal
  from TTS.tts.utils.data import StandardScaler
label_desc: Use image node_id 19 for calling the AudioProcessor obj's underlying member method code with example usage: obj._stft(y) and returns: librosa