Make example about hiding None return values at the prompt clearer.
diff --git a/Doc/tutorial/controlflow.rst b/Doc/tutorial/controlflow.rst
index fa445d3..0f72d3d 100644
--- a/Doc/tutorial/controlflow.rst
+++ b/Doc/tutorial/controlflow.rst
@@ -235,8 +235,9 @@
technically speaking, procedures do return a value, albeit a rather boring one.
This value is called ``None`` (it's a built-in name). Writing the value
``None`` is normally suppressed by the interpreter if it would be the only value
-written. You can see it if you really want to::
+written. You can see it if you really want to using :keyword:`print`::
+ >>> fib(0)
>>> print fib(0)
None