Merge pull request #1892 from tkf/suspicious-quotes

Remove suspicious quotes in interactiveshell.py

IPython/core/interactiveshell.py

@@ -263,7 +263,7 b' class InteractiveShell(SingletonConfigurable):'
         """
     )
     disable_failing_post_execute = CBool(False, config=True,
-        help="Don't call post-execute functions that have failed in the past."""
+        help="Don't call post-execute functions that have failed in the past."
     )
     display_formatter = Instance(DisplayFormatter)
     displayhook_class = Type(DisplayHook)