Actually, we don't know.  This information was not released with any hard proof and, in fact, the NSA stated that it was only a percentage confident, not 100% and probably not provable in court.  

This is all a show perpetrated by both parties to try and just add that period at the end to all the BS statements made during the 2016 election process. Neither party seems willing to just admit that 1) they presented a weak and corrupt candidate produced by a questionable primary process and 2) they then put forth these candidates to the American people via a questionable and at the least an extremely dirty campaign.   Both parties engaged in dirty tricks not seen since those of the Nixon regime and they were caught. Now they are playing the fancy two-step to try and get out from under the increasing skeptical gaze of the American People.