Comment by liaodalin19903 for I don't have a working keystone v3 cloud to check this on, but I have been told a few times that the *_name fields are supposed to be capital "Default" while the equivalent *_id fields are "default". Try switching user_domain_name and project_domain_name to be user_domain_id and project_domain_id. Additionally, I keep seeing your questions in #openstack-sdks but you're never around for the answer. Can you email me at brian at python.org so I can know what you're trying to do here?

Either I change the `user_domain_name` to `user_domain_id` or set the `default` to `Default`, but all no use, so perhaps I should change the sdk to libcloud which document is ample.