Try to discourage use of PyObject_Type().

Doc/api/abstract.tex

@@ -319,6 +319,11 @@ determination.
   the object type of object \var{o}. On failure, raises
   \exception{SystemError} and returns \NULL.  This is equivalent to
   the Python expression \code{type(\var{o})}.
+  This function increments the reference count of the return value.
+  There's really no reason to use this function instead of the
+  common expression \code{\var{o}->ob_type}, which returns a pointer
+  of type \code{PyTypeObject *}, except when the incremented reference
+  count is needed.
   \bifuncindex{type}
 \end{cfuncdesc}