code: def complex(self, x):
      x_stft = torch.stft(
          x,
          self.fft_size,
          self.hop_size,
          self.win_size,
          self.window.type_as(x),
          normalized=self.normalized,
      )
      real = x_stft[..., 0]
      imag = x_stft[..., 1]
      return real, imag
  
imports: import logging
  import math
  from typing import Any, Dict, List, Optional
  import numpy
  import torch
  import torch.nn.functional
  from espnet2.gan_svs.visinger2.ddsp import remove_above_nyquist, scale_function, upsample
  from espnet2.gan_tts.hifigan import HiFiGANMultiPeriodDiscriminator, HiFiGANMultiScaleDiscriminator, HiFiGANMultiScaleMultiPeriodDiscriminator, HiFiGANPeriodDiscriminator, HiFiGANScaleDiscriminator
  from espnet2.gan_tts.hifigan.residual_block import ResidualBlock
label_desc: Use image node_id 3 for calling the TorchSTFT obj's underlying member method code with example usage: obj.complex(x) and returns: real,  imag