code: def transform(self, X):
          
          if isinstance(X, pd.DataFrame):
              X_transformed = X[self.feat_list].values
          elif isinstance(X, np.ndarray):
              X_transformed = X[:, self.feat_list_idx]
  
          return X_transformed.astype(np.float64)
docs: Make subset after fit
  
          Parameters
          ----------
          X: numpy ndarray, {n_samples, n_features}
              New data, where n_samples is the number of samples and n_features is the number of features.
  
          Returns
          -------
          X_transformed: array-like, shape (n_samples, n_features + 1) or (n_samples, n_features + 1 + n_classes) for classifier with predict_proba attribute
              The transformed feature set.