def METHOD_NAME():
    """Assert that the _get_support_mask function returns correct mask."""
    ds = FeatureSetSelector(subset_list="tests/subset_test.csv", sel_subset="test_subset_1")
    ds.fit(test_X, y=None)
    mask = ds._get_support_mask()
    get_mask = ds.get_support()
    assert mask.shape[0] == 30
    assert np.count_nonzero(mask) == 5
    assert np.array_equal(get_mask, mask)