https://git.ufz.de/rdm/minio-cli-wrapper/-/blob/master/minio_cli_wrapper/mc.py#L178
mutable defaults are evil 😈
https://docs.python-guide.org/writing/gotchas/#mutable-default-arguments
https://stackoverflow.com/questions/1132941/least-astonishment-and-the-mutable-default-argument