diff --git a/ryu/cfg.py b/ryu/cfg.py
index 62ce33a7..24959611 100644
--- a/ryu/cfg.py
+++ b/ryu/cfg.py
@@ -36,10 +36,13 @@ CONF = oslo.config.cfg.CONF
 
 # re-export for convenience
 
+from oslo.config.cfg import ConfigOpts
+
 from oslo.config.cfg import BoolOpt
 from oslo.config.cfg import IntOpt
 from oslo.config.cfg import ListOpt
 from oslo.config.cfg import MultiStrOpt
 from oslo.config.cfg import StrOpt
 
+from oslo.config.cfg import RequiredOptError
 from oslo.config.cfg import ConfigFilesNotFoundError