Description of problem: On Fedora 27 (and somewhat earlier too), if otopi finds 'yum', it uses it. See also bug 1495629. Currently, otopi itself starts to support python3 and dnf-2, but the tools that use it (engine-setup, hosted-engine-setup, host-deploy) still do not (fully, at least). Also the interface and desired behavior are not fully clear (e.g. should 'otopi' choose python version, or link to python2-otopi, etc.). Opening this bug mainly so that once everything works with python3/dnf-2, we remove this option - make otopi refuse to use yum if dnf is found. Exact behavior is still TBD. The risk of not fixing this bug is e.g. to have separate dnf and yum histories, etc., perhaps other similar things.
*** This bug has been marked as a duplicate of bug 1542529 ***