These are all the same function: - https://github.com/python-effect/effect/blob/826cbc5b6917683ba6ddf70cd693d3028ecdf226/effect/_test_utils.py#L52 - https://github.com/python-effect/effect/blob/826cbc5b6917683ba6ddf70cd693d3028ecdf226/effect/_base.py#L183 - https://github.com/python-effect/effect/blob/826cbc5b6917683ba6ddf70cd693d3028ecdf226/effect/test_retry.py#L63 so probably some of them should import the one implementation