code: def get_dataset(ds_name, train=True, download=True):
      """Get the auto dataset with `ds_name`.
  
      Parameters
      ----------
      ds_name : str
          The name of dataset, you may view registered with `list_dataset`.
      train : bool, default is `True`
          If `True`, get the training set, if `False`, try to get the validation set.
      download : bool, default is `True`
          If `True`, download the dataset automatically if not found on disk.
  
      """
      if not ds_name in _DATASETS:
          choices = str(_DATASETS.keys())
          raise ValueError(
              "{} not found. Available choices: {}".format(
                  ds_name, choices
              )
          )
      ret = _DATASETS[ds_name](download=download)
      if not isinstance(ret, (list, tuple)):
          if train:
              return ret
          else:
              raise ValueError(
                  "No validation dataset available for {}".format(
                      ds_name
                  )
              )
      if train:
          return ret[0]
      else:
          if len(ret) < 2:
              raise ValueError(
                  "No validation dataset available for {}".format(
                      ds_name
                  )
              )
          return ret[1]
  
file_path: gluon-cv/gluoncv/auto/data/data_zoo.py
imports: import os
  import shutil
  import tarfile
  import zipfile
  from ...data import VOCDetection, COCODetection
  from ...utils import download, makedirs
label_desc: Use image node_id 2 for calling a global function with example usage: get_dataset(ds_name, train, download) and returns: ret, ret, ret