Error: No such command "create-user".

New install. Ubuntu 18.04. Did a sudo pip install burp-ui. All went well. Started server with burp-ui -d -- -h 0.0.0.0 -p 8000 as root. UI comes up in the browser. I tried to add a user. Ran as root:

# bui-manage create-user jkugler
Usage: flask [OPTIONS] COMMAND [ARGS]...

Error: No such command "create-user".

What am I doing wrong? Doc bug? Code bug?