code: def fit(
      self, X: pd.DataFrame, y: pd.Series, s: Optional[pd.Series] = None
  ) -> None:
      pass
  
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 2 for calling the Identity obj's underlying member method code with example usage: obj.fit(X, y, s) without return types