diff --git a/tools/test_pr.py b/tools/test_pr.py
index a2d94d3..10ba02c 100755
--- a/tools/test_pr.py
+++ b/tools/test_pr.py
@@ -1,3 +1,4 @@
+#!/usr/bin/env python
 """
 This is a script for testing pull requests for IPython. It merges the pull
 request with current master, installs and tests on all available versions of