docs: def data(self):
          """Return the examples in the dataset in order, sorted, or shuffled."""
          if self.sort:
              xs = sorted(self.dataset, key=self.sort_key)
          elif self.shuffle:
              xs = [self.dataset[i] for i in self.random_shuffler(range(len(self.dataset)))]
          else:
              xs = self.dataset
          return xs