diff --git a/ryu/lib/of_config/__init__.py b/ryu/lib/of_config/__init__.py
index b3605881..fe24fb9b 100644
--- a/ryu/lib/of_config/__init__.py
+++ b/ryu/lib/of_config/__init__.py
@@ -18,6 +18,8 @@ import glob
 import os.path
 import sys
 
+import ryu.contrib  # we require ncclient
+
 SCHEMA_DIR = os.path.dirname(__file__)
 
 _PREFIX = 'of-config-'