Changed scripts to explicitly use Python 3 only, to avoid
maintaining Python 2.
Removed deprecation notices.

Signed-off-by: Louise Kilheeney <louise.kilheeney@intel.com>
Signed-off-by: Kevin Laatz <kevin.laatz@intel.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Robin Jarry <robin.jarry@6wind.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: Ray Kinsella <mdr@ashroe.eu>