def METHOD_NAME(self):
    """Test that the return type of the observable is :attr:`ObservableReturnTypes.Variance`"""
    dev = qml.device("default.qubit", wires=2)
    @qml.qnode(dev)
    def circuit():
        res = qml.var(qml.PauliZ(0))
        assert res.return_type is Variance
        return res
    circuit()