These may be the shortest-lived sanctions, with Trump taking the presidency in one month.
And, honestly, we all know that there wasn't Russian hacking of the DNC. British diplomat Craig Murray says they met the leaker (not hacker), and that they're not Russian, but are a DNC-insider.
Obama's desperate "retaliation" is him trying to save face for a weak job as president, for which next to nothing remains to stand as his legacy. His legacy is going to be that Trump undid his legacy within months... and abstaining from vetoing the UN council resolution condemning illegal Israeli settlements. That's about it.