def METHOD_NAME(memory_ds):
    ds = memory_ds
    with ds:
        ds.create_tensor("x")
        ds.create_tensor("y")
        ds.x.extend(np.ones((3, 4000, 3000)))
        ds.y.extend(np.ones((3, 4000, 3000)))
    assert len(ds) == 3
    assert len(ds.x) == 3
    assert len(ds.y) == 3