code: def _datapath(opt: Opt) -> str:
      build(opt)
      return os.path.join(opt["datapath"], "cmu_dog")
  
imports: import copy
  import json
  import os
  from enum import Enum
  from typing import List, Optional, Tuple
  from parlai.core.message import Message
  from parlai.core.metrics import F1Metric
  from parlai.core.mutators import EpisodeMutator, MessageMutator, register_mutator
  from parlai.core.opt import Opt
  from parlai.core.params import ParlaiParser
  from parlai.core.teachers import DialogTeacher
  from parlai.tasks.cmu_dog.build import build
  from parlai.tasks.wizard_of_wikipedia.agents import RareWordF1Calculator, TOKEN_KNOWLEDGE, TOKEN_END_KNOWLEDGE
  from parlai.utils.data import DatatypeHelper
  from parlai.utils.io import PathManager
  from parlai.utils.logging import logger
  from parlai.utils.typing import TShared
label_desc: Use image node_id 1 for calling a global function with example usage: _datapath(opt) and returns: os