code: def _update_feature_stats(self, feat_name, feat_val, w):
      if feat_name not in self.nominal_features:
          self._feat_stats[feat_name].update(feat_val, w)
  
imports: from __future__ import annotations
  import collections
  import functools
  import io
  import math
  import typing
  from river import anomaly, base, drift, linear_model, stats
  from river.tree import split_criterion
  from river.tree import splitter
  from .base import HoeffdingRule
label_desc: Use image node_id 6 for calling the RegRule obj's underlying member method code with example usage: obj._update_feature_stats(feat_name, feat_val, w) without return types