'Get a role by its id or name.
For a full list of available parameters, please refer to the official
API reference:
https://developer.openstack.org/api-ref/identity/v2-ext/index.html#show-a-role
OR
https://developer.openstack.org/api-ref/identity/v2-ext/index.html#show-role-information-by-name'

def show_role(self, role_id_or_name):

    (resp, body) = self.get(('OS-KSADM/roles/%s' % role_id_or_name))
    self.expected_success(200, resp.status)
    body = json.loads(body)
    return rest_client.ResponseBody(resp, body)
