code: def _iter_datasets():
      for _, dataset in inspect.getmembers(
          importlib.import_module("river.datasets"), inspect.isclass
      ):
          if issubclass(dataset, datasets.Insects):
              for variant in dataset.variants:
                  yield dataset(variant=variant)
              continue
          yield dataset()
  
file_path: river/river/datasets/test_datasets.py
imports: from __future__ import annotations
  import functools
  import importlib
  import inspect
  import itertools
  from urllib import request
  import pytest
  from river import datasets
  from .None import base
label_desc: Use image node_id 1 for calling a global function with example usage: _iter_datasets() without return types