gistfile1.txt

from keystoneclient import session
from keystoneclient.v2_0 import client as v2_client
from keystoneclient.v3 import client as v3_client

 global _SESSION
    if not _SESSION:
        if cfg.CONF.keystone_authtoken.auth_version == '2':
            client = v2_client
        elif cfg.CONF.keystone_authtoken.auth_version == '3':
            client = v3_client
        else:
            raise Exception('Unknown keystone version!')
        try:
            kc = client.Client(
                auth_url=cfg.CONF.keystone_authtoken.auth_uri,
                username=cfg.CONF.keystone_authtoken.admin_user,
                password=cfg.CONF.keystone_authtoken.admin_password,
                tenant_name=cfg.CONF.keystone_authtoken.admin_tenant_name
            )
            _SESSION = session.Session(auth=kc)
        except Exception:
            with excutils.save_and_reraise_exception():
                LOG.exception(_LE("Error creating Keystone session."))
    return client.Client(session=_SESSION)