I know I've done this before, but it was a few years ago and I can't remember exactly how I did it. Its possible that the notebook has changed in some relevant ways in the meantime.
I'd like to add a bunch of users to a notebook from the commandline. I tried something like this:
users = [['Alice','123'], ['Bob','123'], ['Carol','789']]
nb = sagenb.notebook.notebook.load_notebook('/path/to/my.sagenb/')
nbu = nb.user_manager()
for u in users:
nbu.add_user(u[0],u[1],'',account_type='user',force=True)
nb.save()
But the users do not show up when I start the notebook.