text: """Test Olivetti faces fetcher, if the data is available,
  or if specifically requested via environment variable
  (e.g. for travis cron job)."""
  
  import numpy as np
  
  from sklearn.utils import Bunch
  from sklearn.datasets.tests.test_common import check_return_X_y
  
  from sklearn.utils._testing import assert_array_equal
  
  
  def test_olivetti_faces(fetch_olivetti_faces_fxt):
      data = fetch_olivetti_faces_fxt(shuffle=True, random_state=0)
  
      assert isinstance(data, Bunch)
      for expected_keys in ("data", "images", "target", "DESCR"):
          assert expected_keys in data.keys()
  
      assert data.data.shape == (400, 4096)
      assert data.images.shape == (400, 64, 64)
      assert data.target.shape == (400,)
      assert_array_equal(np.unique(np.sort(data.target)), np.arange(40))
  
      # test the return_X_y option
      check_return_X_y(data, fetch_olivetti_faces_fxt)
  