Comment 2 for bug 1417975

As I said, in order to reproduce this I just used the python client and issued two different calls at the same time (without even using a script, I actually just switched shells and ran the commands manually) - and again, it doesn't happen most of the time, but it does happen every now and again (obviously, a timing issue).

(also it might be better to verify this not via Horizon? I haven't used Horizon for verification afterwards, but rather used the clients to query the server for its security groups)