docstr: Update data directories
  
  Args:
      data_dir: path to data directory
      dialogues_example_dir: path to preprocessed dialogues example directory, if not exists will be created.
docstr_tok: ["Update","data","directories","Args",":","data_dir",":","path","to","data","directory","dialogues_example_dir",":","path","to","preprocessed","dialogues","example","directory",",","if","not","exists","will","be","created","."]
code: def update_data_dirs(self, data_dir: str, dialogues_example_dir: str):
      """
      Update data directories
  
      Args:
          data_dir: path to data directory
          dialogues_example_dir: path to preprocessed dialogues example directory, if not exists will be created.
      """
      if not os.path.exists(data_dir):
          raise ValueError(f"{data_dir} is not found")
      self._cfg.dataset.data_dir = data_dir
      self._cfg.dataset.dialogues_example_dir = dialogues_example_dir
      logging.info(f"Setting model.dataset.data_dir to {data_dir}.")
      logging.info(
          f"Setting model.dataset.dialogues_example_dir to {dialogues_example_dir}."
      )
  
imports: import collections
  import copy
  import os
  import random
  from typing import Dict, Optional, Union
  import numpy
  import torch
  from omegaconf import DictConfig
  from pytorch_lightning import Trainer
  from torch.utils.data import DataLoader
  from transformers import AutoModelWithLMHead
  from nemo.collections.nlp.data.dialogue import DialogueGPTClassificationDataset, DialogueSGDDataProcessor
  from nemo.collections.nlp.data.dialogue.data_processor.assistant_data_processor import DialogueAssistantDataProcessor
  from nemo.collections.nlp.data.dialogue.data_processor.design_data_processor import DialogueDesignDataProcessor
  from nemo.collections.nlp.metrics.classification_report import ClassificationReport
  from nemo.collections.nlp.metrics.dialogue_metrics import DialogueClassificationMetrics
  from nemo.collections.nlp.models.language_modeling.megatron_gpt_model import MegatronGPTModel
  from nemo.collections.nlp.models.language_modeling.megatron_gpt_prompt_learning_model import MegatronGPTPromptLearningModel
  from nemo.collections.nlp.models.nlp_model import NLPModel
  from nemo.collections.nlp.modules.common import VirtualPromptSource, VirtualPromptStyle
  from nemo.collections.nlp.modules.common.text_generation_utils import get_default_sampling_params, megatron_gpt_generate
  from nemo.collections.nlp.modules.common.transformer.text_generation import LengthParam
  from nemo.collections.nlp.parts.nlp_overrides import NLPSaveRestoreConnector
  from nemo.core.classes.common import PretrainedModelInfo
  from nemo.utils import logging
label_desc: Use image node_id 26 for calling the DialogueGPTClassificationModel obj's underlying member method code with example usage: obj.update_data_dirs(data_dir, dialogues_example_dir) without return types