code: def double_dataframe_column(self, df: pd.DataFrame) -> pd.DataFrame:
      assert isinstance(df, pd.DataFrame)
      return df[["col1"]] * 2
  
file_path: BentoML/tests/e2e/bento_server_grpc/python_model.py
imports: from __future__ import annotations
  from typing import TYPE_CHECKING
  from typing import Any
  import numpy
  import pandas
label_desc: Use image node_id 6 for calling the PythonFunction obj's underlying member method code with example usage: obj.double_dataframe_column(df) and returns: unknown