code: def _score_core_from_prediction(
      self,
      actual_series: TimeSeries,
      pred_series: TimeSeries,
  ) -> TimeSeries:
      self._assert_deterministic(actual_series, "actual_series")
      self._assert_deterministic(pred_series, "pred_series")
      return actual_series - pred_series
  
imports: from darts.ad.scorers.scorers import NonFittableAnomalyScorer
  from darts.timeseries import TimeSeries
label_desc: Use image node_id 3 for calling the DifferenceScorer obj's underlying member method code with example usage: obj._score_core_from_prediction(actual_series, pred_series) and returns: unknown