code: def fit(self, X: np.ndarray, y: np.ndarray) -> "OLS":
      self.stat_model_fit = self.stat_model(y, X).fit()
      SklearnModel.fit(self, X, self.stat_model_fit.resid)
      return self
  
file_path: imodels/imodels/experimental/bartpy/extensions/ols.py
imports: from typing import Type
  import numpy
  from ..sklearnmodel import SklearnModel
label_desc: Use image node_id 2 for calling the OLS obj's underlying member method code with example usage: obj.fit(X, y) and returns: self