constructor({ alphas }) {
        super();
        this.alphas = alphas;
    }
@param {Object} output The output of the model.
@param {Tensor} output.waveform The final audio waveform predicted by the model, of shape `(batch_size, sequence_length)`.
@param {Tensor} output.spectrogram The log-mel spectrogram predicted at the output of the flow model.
This spectrogram is passed to the Hi-Fi GAN decoder model to obtain the final audio waveform.