Open Stack

Hi!  I'm looking for a way to see which users are associated with which 
projects.  The dashboard does it pretty nicely, but I'd prefer from the 
CLI.  Unfortunately, while "openstack role assignment list" seems to be 
what I'd want, it requires *both* a project and a user, which means that 
in order to map everything, I'd have to iterate through every project 
for every user -- about as inefficient a way as I can imagine.  Surely 
there's a better way?

Thanks,

-Ken