def METHOD_NAME(self, batch, stage):
    "Given an input batch it computes the output probabilities."
    batch = batch.to(self.device)
    wavs, lens = batch.sig
    feats = self.modules.compute_features(wavs)
    feats = self.modules.mean_var_norm(feats, lens)
    x = self.modules.model(feats)
    x = self.modules.lin(x)
    outputs = self.hparams.softmax(x)
    return outputs, lens