Added a missing is

mitsuhiko · mitsuhiko · commit 6b5ba145213d · 2010-08-10T23:10:55.000+02:00
diff --git a/docs/patterns/flashing.rst b/docs/patterns/flashing.rst
@@ -14,7 +14,7 @@ template that does this.
 Simple Flashing
 ---------------
 
-So here a full example::
+So here is a full example::
 
     from flask import flash, redirect, url_for, render_template
 
