Change markup so it generates a link

Doc/library/__future__.rst

@@ -26,7 +26,7 @@ Each statement in :file:`__future__.py` is of the form::
 
 
 where, normally, *OptionalRelease* is less than *MandatoryRelease*, and both are
-5-tuples of the same form as ``sys.version_info``::
+5-tuples of the same form as :data:`sys.version_info`::
 
    (PY_MAJOR_VERSION, # the 2 in 2.1.0a3; an int
     PY_MINOR_VERSION, # the 1; an int

Doc/library/sys.rst

@@ -447,8 +447,8 @@ always available.
 
    This is called ``hexversion`` since it only really looks meaningful when viewed
    as the result of passing it to the built-in :func:`hex` function.  The
-   ``version_info`` value may be used for a more human-friendly encoding of the
-   same information.
+   struct sequence  :data:`sys.version_info` may be used for a more human-friendly
+   encoding of the same information.
 
 
 .. data:: int_info