code: def test_loader_download(tmpdir, loader):
      """
      Test download of dataset when it does not exist (requires Internet connection!)
      """
      name = loader.__name__[len("load_") :]
      data_home = str(tmpdir.mkdir("datasets"))
  
      # The dataset should not exist
      assert not dataset_exists(name, data_home=data_home)
      assert not dataset_archive(
          name, DATASETS[name]["signature"], data_home=data_home
      )
  
      # Load the dataset
      loader(data_home=data_home)
  
      # The dataset should have been downloaded
      assert dataset_exists(name, data_home=data_home)
      assert dataset_archive(
          name, DATASETS[name]["signature"], data_home=data_home
      )
  
imports: import pytest
  from yellowbrick.datasets.loaders import *
  from yellowbrick.datasets.loaders import DATASETS
  from yellowbrick.datasets.path import dataset_exists, dataset_archive
label_desc: Use image node_id 1 for calling a global function with example usage: test_loader_download(tmpdir, loader) without return types