diff --git a/tools/ct_metrics/gen_csv_results.py b/tools/ct_metrics/gen_csv_results.py
index 78b323d..342fe69 100755
--- a/tools/ct_metrics/gen_csv_results.py
+++ b/tools/ct_metrics/gen_csv_results.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 r"""
 Use robot framework API to extract test result data from output.xml generated