docs: def get_statistics(self):
          """Get all statistics as a dictionary.
  
          Returns
          -------
          statistics : Dict[str, List]
          """
          return {
              'cumulative_elapsed_time': self.get_cumulative_elapsed_time(),
              'percentage': self.get_percentage(),
              'n_splits': self.get_n_splits(),
              'mean_per_split': self.get_mean_per_split(),
          }