def ordered_indices(self):
        """Return an ordered list of indices. Batches will be constructed based
        on this order."""
        if self.shuffle:
            order = [np.random.permutation(len(self))]
        else:
            order = [np.arange(len(self))]
        order.append(self.sizes)
        return np.lexsort(order)
Return an ordered list of indices. Batches will be constructed based
        on this order.
understand_icl/fairseq/fairseq/data/monolingual_dataset.py