diff --git a/library/juju_facts.py b/library/juju_facts.py
index 4ae84db..ca24f0e 100644
--- a/library/juju_facts.py
+++ b/library/juju_facts.py
@@ -16,6 +16,7 @@
 
 import json
 import subprocess
+import sys
 
 def dict_keys_dash_to_underscore(dashed):
     underscored = dict((k.replace('-','_'),v) for k,v in dashed.items())