code: def transform(
      self,
      X: pd.DataFrame,
      y: pd.Series,
      s: Optional[pd.Series] = None,
  ) -> tuple[pd.DataFrame, pd.Series, Optional[pd.Series]]:
      return X, y, s
  
file_path: aequitas/src/aequitas/fairflow/methods/preprocessing/identity.py
imports: from typing import Optional
  import pandas
  from .preprocessing import PreProcessing
label_desc: Use image node_id 3 for calling the Identity obj's underlying member method code with example usage: obj.transform(X, y, s) and returns: X,  y,  s