class_docstr: Dataset for Causal Language modeling.
docstr: Quick check whether Dataframe and configurations are correctly set.
docstr_tok: ["Quick","check","whether","Dataframe","and","configurations","are","correctly","set","."]
code: def sanity_check(
      cls, df: pd.DataFrame, cfg: Any, mode: str = "train"
  ):
      """
      Quick check whether Dataframe and configurations are correctly set.
      """
      if (
          cfg.dataset.parent_id_column is not None
          and cfg.dataset.parent_id_column in df.columns
          and "id" in df.columns
      ):
          assert (
              df[cfg.dataset.parent_id_column] != df["id"]
          ).all(), (
              "Parent id column is the same as id column for some rows"
          )
          assert (
              df[cfg.dataset.parent_id_column].fillna("") == ""
          ).sum() > 0, (
              "Did not find any conversation start. "
              "Please ensure that some parent ids are empty."
          )
  
      assert cfg.dataset.answer_column in df.columns, (
          f"Answer column {cfg.dataset.answer_column} not found in the "
          f"{mode} DataFrame."
      )
      assert (
          df.shape[0]
          == df[[cfg.dataset.answer_column]].dropna().shape[0]
      ), (
          f"The {mode} DataFrame"
          f" column {cfg.dataset.answer_column}"
          " contains missing values."
      )
      if cfg.dataset.parent_id_column != "None":
          assert (
              "id" in df.columns
          ), "When using parent column, the dataframe requires an 'id' column. "
  
imports: import codecs
  import collections.abc
  import logging
  from typing import Any, Dict, List, Tuple, Union
  import numpy
  import pandas
  import torch
  from torch.utils.data import Dataset
  from llm_studio.src.datasets.conversation_chain_handler import ConversationChainHandler
  from llm_studio.src.datasets.text_utils import get_tokenizer
label_desc: Use image node_id 14 for calling the CustomDataset obj's underlying member method code with example usage: obj.sanity_check(cls, df, cfg, mode) without return types