juju 1.x add machine command: how to specify flavors in an openstack environment

[Eddy Truyen]

Hey,

How can I  specify in juju1 in the `juju machine add` command the type 
of flavor (number of virtual cpus, GB of RAM).?

I work in an openstack environment. As far as I can see I can only 
specify desired memory: juju machine add --constraints mem=8G

but how do I specify the number of virtual cpus?

Best

Eddy