 shape (nb_samples, nb_channels, nb_bins, nb_frames, complex=2)
            last axis is stacked real and imaginary
    &#34;&#34;&#34;

    shape = x.size()
    nb_samples, nb_channels, nb_timesteps = shape

    # pack batch
    x = x.view(-1, shape[-1])

    stft_f = torch.stft(
        x,
        n_fft=self.n_fft,
        hop_length=self.n_hop,
        window=self.window,
        center=self.center,
        normalized=False,
        onesided=True,
        pad_mode=&#34;reflect&#34;,
    )

    # unpack b