Option "os_region_name" is not in the default configuration file

[subcrew]

$ kubespray --version                                                                                                                                                   kubespray 0.5.2
$ kubespray openstack --nodes 3                                                                                                                                         17:13:13
[WARNING]: A directory /home/hhh/.kubespray already exists

Are you sure to overwrite it ? [Y/n] y

CLONING KUBESPRAY GIT REPO *****************************************************
Cloning into '/home/hhh/.kubespray'...
kubespray repo cloned
Traceback (most recent call last):
  File "/home/hhh/.local/bin/kubespray", line 422, in <module>
    args.func(config)
  File "/home/hhh/.local/bin/kubespray", line 65, in openstack
    O.gen_openstack_playbook()
  File "/home/hhh/.local/lib/python2.7/site-packages/kubespray/cloud.py", line 327, in gen_openstack_playbook
    'region_name': self.options['os_region_name'],
KeyError: 'os_region_name'