diff --git a/serve.py b/serve.py
index eb9b51c..9fe6895 100644
--- a/serve.py
+++ b/serve.py
@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 from http import server # Python 3
+import os
 
 class MyHTTPRequestHandler(server.SimpleHTTPRequestHandler):
         def end_headers(self):