SF patch 499062: Minor typo in test_generators.py.
There's no actual patch there.  It's an objection that Guido's example
doesn't actually generator "leaves", so change the comment that says
it does.
diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py
index 2c319e5..155a83c 100644
--- a/Lib/test/test_generators.py
+++ b/Lib/test/test_generators.py
@@ -259,7 +259,7 @@
     >>> # Show it off: create a tree.
     >>> t = tree("ABCDEFGHIJKLMNOPQRSTUVWXYZ")
 
-    >>> # A recursive generator that generates Tree leaves in in-order.
+    >>> # A recursive generator that generates Tree labels in in-order.
     >>> def inorder(t):
     ...     if t:
     ...         for x in inorder(t.left):