On May 1, 2019, @KamalaHarris asked Bill Barr if Trump ever asked or suggested that he opened an investigation into anyone. Bill Barr stalled by grappling with the word "suggest."
Now we know the answer.
April 21: Trump called Zelensky (to congratulate on win)
April 25: Biden announces candidacy
May 1: NYT reported that Giuliani had been urging Ukraine to conduct an investigation into Bidens: nytimes.com/2019/05/01/us/…