diff --git a/rdflib/extras/external_graph_libs.py b/rdflib/extras/external_graph_libs.py
index 25c745c02..873805b48 100644
--- a/rdflib/extras/external_graph_libs.py
+++ b/rdflib/extras/external_graph_libs.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env
+#!/usr/bin/env python
 # encoding: utf-8
 from __future__ import absolute_import
 from __future__ import division