code: def __len__(self):
      self._check_current_dataloader()
      return len(self.current_dataloader)
  
imports: import csv
  import json
  import logging
  import os
  import warnings
  from dataclasses import dataclass, field
  from typing import List
  import pytorch_lightning
  from mmf.common.registry import registry
  from mmf.common.sample import convert_batch_to_sample_list
  from mmf.utils.configuration import get_mmf_env
  from mmf.utils.distributed import gather_tensor, is_main
  from mmf.utils.file_io import PathManager
  from mmf.utils.general import ckpt_name_from_core_args, foldername_from_config_override
  from mmf.utils.logger import log_class_usage
  from mmf.utils.timer import Timer
  from omegaconf import OmegaConf
  from torch.utils.data import Dataset
label_desc: Use image node_id 10 for calling the TestReporter obj's underlying member method code with example usage: obj.__len__() and returns: len