From 26a174e208a6ba001ba6c4564dbf896b90a360ed 2014-01-16 10:57:00
From: Jonathan Frederic <jon.freder@gmail.com>
Date: 2014-01-16 10:57:00
Subject: [PATCH] Added check on widget close to make sure comm isn't already none.

---

diff --git a/IPython/html/widgets/widget.py b/IPython/html/widgets/widget.py
index 687742a..47c2150 100644
--- a/IPython/html/widgets/widget.py
+++ b/IPython/html/widgets/widget.py
@@ -98,8 +98,11 @@ class Widget(LoggingConfigurable):
         """Close method.  Closes the widget which closes the underlying comm.
         When the comm is closed, all of the widget views are automatically 
         removed from the frontend."""
-        self._comm.close()
-        del self._comm
+        try:
+            self._comm.close()
+            del self._comm
+        except:
+            pass # Comm doesn't exist and/or is already closed.
     
     
     # Properties