code: def __init__(self, estimator: sklearn_base.BaseEstimator):
      self.estimator = estimator
      self._feature_names: list | None = None
  
imports: from __future__ import annotations
  import copy
  import functools
  import pandas
  from sklearn import base
  from sklearn import exceptions
  from river import base
label_desc: Use image node_id 1 to create a new SKL2RiverBase object  with example: obj = SKL2RiverBase(estimator)