From bb73f4ab46c456fac01024792dc71b38a2e8f613 Mon Sep 17 00:00:00 2001
From: dessant <dessant@users.noreply.github.com>
Date: Mon, 20 Oct 2014 23:03:53 +0300
Subject: [PATCH] make doc autobuild.py work under python 3

---
 doc/autobuild.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/doc/autobuild.py b/doc/autobuild.py
index c64faa30d..54b9ef72e 100644
--- a/doc/autobuild.py
+++ b/doc/autobuild.py
@@ -167,7 +167,7 @@ template_examples_ref = ('# :ref:`Jump directly to Examples'
 
 def extract_summary_line(doc):
     if doc is None:
-        return
+        return ''
     for line in doc.split('\n'):
         line = line.strip()
         # don't take empty line