def test_view_of_view(matrix_type, subset_func, subset_func2):
    adata = gen_adata((30, 15), X_type=matrix_type)
    adata.raw = adata
    if subset_func is single_subset:
        pytest.xfail("Other subset generating functions have trouble with this")
    var_s1 = subset_func(adata.var_names, min_size=4)
    var_view1 = adata[:, var_s1]
    var_s2 = subset_func2(var_view1.var_names)
    var_view2 = var_view1[:, var_s2]
    assert var_view2._adata_ref is adata
    obs_s1 = subset_func(adata.obs_names, min_size=4)
    obs_view1 = adata[obs_s1, :]
    obs_s2 = subset_func2(obs_view1.obs_names)
    assert adata[obs_s1, :][:, var_s1][obs_s2, :]._adata_ref is adata

    view_of_actual_copy = adata[:, var_s1].copy()[obs_s1, :].copy()[:, var_s2].copy()

    view_of_view_copy = adata[:, var_s1][obs_s1, :][:, var_s2].copy()

    assert_equal(view_of_actual_copy, view_of_view_copy, exact=True)
def _storage(self):
        """
        Return the configured django storage backend.
        """
        config = settings.VERIFY_STUDENT["SOFTWARE_SECURE"]

        # Default to the S3 backend for backward compatibility
        storage_class = config.get("STORAGE_CLASS", "storages.backends.s3boto.S3BotoStorage")
        storage_kwargs = config.get("STORAGE_KWARGS", {})

        # Map old settings to the parameters expected by the storage backend
        if "AWS_ACCESS_KEY" in config:
            storage_kwargs["access_key"] = config["AWS_ACCESS_KEY"]
        if "AWS_SECRET_KEY" in config:
            storage_kwargs["secret_key"] = config["AWS_SECRET_KEY"]
        if "S3_BUCKET" in config:
            storage_kwargs["bucket"] = config["S3_BUCKET"]
            storage_kwargs["querystring_expire"] = self.IMAGE_LINK_DURATION

        return get_storage(storage_class, **storage_kwargs)