def test_layers_view():
    X = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])
    L = np.array([[10, 11, 12], [13, 14, 15], [16, 17, 18]])
    real_adata = ad.AnnData(X)
    real_adata.layers["L"] = L
    view_adata = real_adata[1:, 1:]
    real_hash = joblib.hash(real_adata)
    view_hash = joblib.hash(view_adata)

    assert view_adata.is_view

    with pytest.raises(ValueError):
        view_adata.layers["L2"] = L + 2

    assert view_adata.is_view  # Failing to set layer item makes adata not view
    assert real_hash == joblib.hash(real_adata)
    assert view_hash == joblib.hash(view_adata)

    view_adata.layers["L2"] = L[1:, 1:] + 2

    assert not view_adata.is_view
    assert real_hash == joblib.hash(real_adata)
    assert view_hash != joblib.hash(view_adata)
def create_snapshot(self, volume_id, **kwargs):
        """
        Creates a new snapshot.
        volume_id(Required): id of the volume.
        force: Create a snapshot even if the volume attached (Default=False)
        display_name: Optional snapshot Name.
        display_description: User friendly snapshot description.
        """
        post_body = {'volume_id': volume_id}
        post_body.update(kwargs)
        post_body = json.dumps({'snapshot': post_body})
        resp, body = self.post('snapshots', post_body)
        body = json.loads(body)
        return resp, body['snapshot']