[PATCH 2 of 2] py3: build help of compression engines in bytes

[Augie Fackler]

> On Oct 13, 2018, at 14:28, Yuya Nishihara <yuya at tcha.org> wrote:
> 
> # HG changeset patch
> # User Yuya Nishihara <yuya at tcha.org>
> # Date 1539433045 -7200
> #      Sat Oct 13 14:17:25 2018 +0200
> # Node ID 921feabe152110773b8b85818b149a99166b9f74
> # Parent  b8a16cf84c34d254df7ff276e49e6d5fd327eb8b
> py3: build help of compression engines in bytes

queued, thanks