diff --git a/nvchecker/tools.py b/nvchecker/tools.py
index 31fe87a..e2c7223 100644
--- a/nvchecker/tools.py
+++ b/nvchecker/tools.py
@@ -1,6 +1,7 @@
 # vim: se sw=2:
 
 import sys
+import os
 import argparse
 import logging