Comment 33 for bug 1620696

After debugging a lot inside heat i didn't understand what is the cause that was making heat use 2015-04-30 version instead of 2016-10-14 for that specific list_join.
While debugging i've seen other calls to list_join that were resolved correctly (maybe from other files, maybe new files included)

The only way i found to move on from this blocking problem has been changing this row:

https://github.com/openstack/heat/blob/stable/newton/heat/engine/hot/template.py#L300

from

'list_join': hot_funcs.Join,

to:

'list_join': hot_funcs.JoinMultiple,

Is a bad workaround, but i haven't seen other ways to continue up to now.