- Added a fallback to urllib2 for python2

- included urlopen call in a try/except block to avoid crash
when no internet connection is available

IPython/lib/display.py

@@ -263,8 +263,14 b' class YouTubeVideo(IFrame):'
         super(YouTubeVideo, self).__init__(src, width, height, **kwargs)
     
     def _repr_jpeg_(self):
-        from urllib import urlopen
+        try:
+            from urllib.request import urlopen  # Py3
+        except ImportError:
+            from urllib2 import urlopen
+        try:
         return urlopen("https://img.youtube.com/vi/{id}/hqdefault.jpg".format(id=self.id)).read()
+        except IOError:
+            return None
 
 class VimeoVideo(IFrame):
     """