This change also switches dstat to python3. The patches introduced in this
commit are inspired by archlinux[0][1].
[0]:
e688b126c5/trunk/PKGBUILD
[1]: https://git.archlinux.org/svntogit/community.git/tree/trunk/PKGBUILD?h=packages/dstat&id=e688b126c561e842b459ea1cc88e725f1f2a29cc