def METHOD_NAME(self) -> Dataset:
    dataset_file = os.path.join(self.data_dir, "gdb9.sdf")
    if not os.path.exists(dataset_file):
        dc.utils.data_utils.download_url(url=GDB9_URL,
                                         dest_dir=self.data_dir)
        dc.utils.data_utils.untargz_file(
            os.path.join(self.data_dir, "gdb9.tar.gz"), self.data_dir)
    loader = dc.data.SDFLoader(tasks=self.tasks,
                               featurizer=self.featurizer,
                               sanitize=True)
    return loader.METHOD_NAME(dataset_file, shard_size=4096)