class_docstr: Map anything to emptiness.
class_docstr_tok: ["Map","anything","to","emptiness","."]
code: def __getitem__(self, idx):
      _ = self.ds[idx]
      return [0]
  
imports: import logging
  import numpy
  from itertools import count
  from typing import List, Tuple
  import torch
  import tqdm
  from fvcore.common.timer import Timer
  from detectron2.utils import comm
  from .build import build_batch_data_loader
  from .common import DatasetFromList, MapDataset
  from .samplers import TrainingSampler
label_desc: Use image node_id 3 for calling the _EmptyMapDataset obj's underlying member method code with example usage: obj.__getitem__(idx) and returns: list