class_docstr: echo transformer
class_docstr_tok: ["echo","transformer"]
code: def transform(self, input_df, is_train=True):
      train_x = input_df[self.feature_cols]
      train_y = input_df[[self.target_col]]
      return train_x, train_y
  
file_path: BigDL/python/chronos/src/bigdl/chronos/autots/deprecated/feature/identity_transformer.py
imports: from bigdl.chronos.autots.deprecated.feature.utils import save_config
  from bigdl.chronos.autots.deprecated.feature.abstract import BaseFeatureTransformer
label_desc: Use image node_id 3 for calling the IdentityTransformer obj's underlying member method code with example usage: obj.transform(input_df, is_train) and returns: train_x,  train_y