diff --git a/development/pdbconv.py b/development/pdbconv.py
index 01bfaac2f..3cdf20e13 100644
--- a/development/pdbconv.py
+++ b/development/pdbconv.py
@@ -3,6 +3,7 @@ import binascii
 import datetime
 import json
 import logging
+import os
 import sys
 import tempfile
 from typing import Dict