code: def fold_size(fold):
      return DATA_LEN[fold]
  
imports: import copy
  import json
  import os
  from typing import Optional
  import numpy
  import pandas
  import parlai.core.tod.tod_agents
  import parlai.core.tod.tod_core
  import parlai.tasks.multiwoz_v22.build
  from parlai.core.message import Message
  from parlai.core.metrics import AverageMetric
  from parlai.core.opt import Opt
  from parlai.core.params import ParlaiParser
  from parlai.utils.data import DatatypeHelper
  from parlai.utils.io import PathManager
  from parlai.utils.testing import is_this_circleci
label_desc: Use image node_id 1 for calling a global function with example usage: fold_size(fold) and returns: DATA_LEN