diff --git a/dataset/freeze/config.py b/dataset/freeze/config.py
index bb5756c..5418ff3 100644
--- a/dataset/freeze/config.py
+++ b/dataset/freeze/config.py
@@ -1,6 +1,8 @@
 import json
 import yaml
 
+from dataset.util import FreezeException
+
 
 TRUISH = ['true', 'yes', '1', 'on']