From fa154d1dbe3c8dec53c227e3c19b586516e17c43 Mon Sep 17 00:00:00 2001
From: Philipp Hagemeister <phihag@phihag.de>
Date: Fri, 21 Mar 2014 17:35:11 +0100
Subject: [PATCH] [videolectures.net] Make description optional

---
 youtube_dl/extractor/videolecturesnet.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/youtube_dl/extractor/videolecturesnet.py b/youtube_dl/extractor/videolecturesnet.py
index f8b946a88..ebd2a3dca 100644
--- a/youtube_dl/extractor/videolecturesnet.py
+++ b/youtube_dl/extractor/videolecturesnet.py
@@ -36,7 +36,10 @@ class VideoLecturesNetIE(InfoExtractor):
         smil = self._download_xml(smil_url, video_id)
 
         title = find_xpath_attr(smil, './/meta', 'name', 'title').attrib['content']
-        description = find_xpath_attr(smil, './/meta', 'name', 'abstract').attrib['content']
+        description_el = find_xpath_attr(smil, './/meta', 'name', 'abstract')
+        description = (
+            None if description_el is None
+            else description_el.attrib['content'])
         upload_date = unified_strdate(
             find_xpath_attr(smil, './/meta', 'name', 'date').attrib['content'])