I'm sure i have read that the following (or something that implies this) is true

> Let $X$ be a $\Pi_1^0$ class with top medvedev degree. Then for every
> $x\in X$, there is $y\in X$ with $y<_T x$.

But i don't remeber where. If this is true, do you know where can I find this or a similar statement?
Thanks