Trying to fix some indents in doc

doc/topics/function.txt

@@ -80,7 +80,7 @@ The ``inputs`` argument to ``theano.function`` is a list, containing the ``Varia
         container's content with an input value provided by the user).
         This means a function will create its own container, and will copy in
         it the content of ``value`` at call time when ``value`` is a container.
-            Updates (if ``update`` is not None) will be stored into the ``value``
+        Updates (if ``update`` is not ``None``) will be stored into the ``value``
         container and not in the function container (which will be filled
         with ``None`` instead, to make sure noone tries to use it by mistake).
             ``None``: Automatically choose between ``True`` or ``False`` depending on the