code: def __init__(
      self,
      schema: Dict[str, Type],
      id_col: str,
      train_df: Optional[DataFrame] = None,
      eval_df: Optional[DataFrame] = None,
      test_df: Optional[DataFrame] = None,
      column_mapping: Dict[str, str] = (),
  ):
      schema[id_col] = str
      super().__init__(
          schema=schema,
          train_df=train_df,
          test_df=test_df,
          eval_df=eval_df,
          column_mapping=column_mapping,
          id_col=id_col,
      )
      self._validate_schema()
  
file_path: pytext/pytext/data/sources/pandas.py
imports: from typing import Dict, Optional, Type
  from pandas import DataFrame
  from pytext.data.sources.data_source import RootDataSource
  from .session import SessionDataSource
label_desc: Use image node_id 1 to create a new SessionPandasDataSource object from inherited base classes: PandasDataSource, SessionDataSource with example: obj = SessionPandasDataSource(schema, id_col, train_df, eval_df, test_df, column_mapping)