normalize shebang lines to #!/usr/bin/env python
diff --git a/Doc/includes/email-alternative.py b/Doc/includes/email-alternative.py
index 82e3ffa..82d605e 100644
--- a/Doc/includes/email-alternative.py
+++ b/Doc/includes/email-alternative.py
@@ -1,4 +1,4 @@
-#! /usr/bin/python
+#!/usr/bin/env python
 
 import smtplib