code: def _register_dataset(ds_name, fn):
      if ds_name in _DATASETS:
          raise ValueError("{} already been registered".format(ds_name))
      assert callable(fn), "register with non-function is not allowed"
      _DATASETS[ds_name] = fn
  
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 3 for calling a global function with example usage: _register_dataset(ds_name, fn) without return types