In his request to Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden and his son Hunter, President Donald Trump used language mimicking that of Fox News host Sean Hannity. Hannity is a sometime presidential adviser whose program Trump watches regularly and who has frequently promoted distortions of the story. 

In what the White House has billed as a memorandum of their July 25 conversation, Trump told Zelensky, “I heard you had a prosecutor who was very good and he was shut down and that’s really unfair.” He later added:

Trump was baselessly suggesting that in 2016, Joe Biden corruptly pushed the Ukrainian government to force out former Ukrainian Prosecutor General Viktor Shokin in order to benefit his son, who worked for a Ukrainian gas company that conservatives have claimed was under investigation. In fact, Biden acted in response to widespread international criticism of Shokin’s lax anticorruption efforts, and the investigation into the company had reportedly been shuttered for more than a year at the time. 

Trump’s claim that “Biden went around bragging that he stopped the prosecution” is apparently a reference to Biden’s description of his effort to force Shokin’s removal during a January 2018 event.

The president’s language may reflect that of one of his closest media allies. In the months leading up to Trump’s call with Zelenskyy, Hannity referred to Biden “bragging” or having “bragged” about getting Shokin fired at least 14 times on 10 episodes of his Fox News show (all transcripts via Nexis; reairings on different dates included; emphasis added):

April 3:

SEAN HANNITY (HOST): When that company came under investigation over corruption claims in Ukraine, Biden used his influence as vice president of the most powerful country on earth. He actually got the lead Ukrainian prosecutor fired and he bragged about it. There's a little detail we will tell you on the other side. Take a look at him bragging.

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Now, the prosecutor that he demanded gets fired or he will not give them a billion dollars and they got six hours to make a decision and he is on tape as you just heard bragging.

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But in this particular case, the vice president of the United States tells them, you fire the prosecutor and we know beyond any doubt that that prosecutor that he has bragging about that he got fired -- he was going to use American taxpayer money as leverage, that he did it to save his son from the prosecutor was investigating him?

April 8:

HANNITY: And we also had the Hillary bought and paid for dossier. Real Russian collusion paid for to influence the election. Now we've got the - we've got evidence. Ukraine - the Ukrainian officials on them with evidence and a tape Joe Biden bragging they fired him.

April 25:

HANNITY: Breaking tonight also, if you remember, John Solomon explained on this program while Joe Biden was vice president, his son Hunter took a lucrative job at a major Ukrainian energy company and by the way is also Peter Schweizer on the China deal. But when the company became the subject of a corruption probe in the country, well, Biden used his influence and your money to literally get the lead prosecutor fired, bragged about it, we'll play the tape. As Solomon reported, the prosecutor was actually investigating Biden's son. 

...

Let me ask you this because we showed the first tape of Joe Biden. Now, how certain are we that they have evidence of this prosecutor that he was telling on tape, bragging about having gotten fired using American money, how certain are we that that prosecutor was investigating his son at the time?

May 6:

HANNITY: And don't forget of course allegations of international corruption that continue to creep closer and closer to his son and his work in Ukraine and in China. Remember Joe Biden, we have him on tape, bragging about getting the Ukrainian prosecutor fired or else he's withholding a billion taxpayer dollars.

May 9:

HANNITY: While Biden was Vice President, well, his son Hunter took a lucrative job at a major Ukrainian energy company, and when the company became the subject of a corruption probe in that country, Biden then used his influence to get the lead prosecutor fired.

He even bragged about it. Remember? Prosecutor was investigating Biden's son. Biden used the threat of pulling $1 billion U.S. aid if they didn't fire the prosecutor in six hours.

May 14:

HANNITY: Unbelievable story. And him bragging on tape about holding American money hostage, not telling that little part about his son and the amount of money both in China, Ukraine and the attempt to influence our election

May 27:

HANNITY: Tonight, as The Hill's John Solomon explained, while Biden was vice president, well, his son hunter took a lucrative job at a major Ukrainian energy company. When the company became the subject of a corruption probe in that country, Biden then used his influence to get the lead prosecutor fired. He even bragged about it. Remember?

The prosecutor was investigating Biden's son. Biden used the threat of pulling $1 billion in U.S. aid if they didn't fire the prosecutor in six hours.

June 5:

HANNITY: All right. Don't forget, the spotlight also shines bright on Biden's shady dealings in places like China, Ukraine, The Hill's John Solomon reported back in 2014, Biden's son, he had that lucrative gig at a Ukrainian energy company. When the company became the subject of a corruption probe in the country, yes, Joe Biden gave them six hours using your tax money, a billion dollars, to get the lead prosecutor fired, even bragged about it.

June 12:

HANNITY: And The Hill's John Solomon reporting. Biden faces serious pay-to-play allegations surrounding his son's dealings with Ukraine and China. Remember Biden bragging on tape about getting the Ukrainian prosecutor fired, the one investigating his son?

July 8:

HANNITY: Biden even once bragged that he used his influences as vice president to get a Ukrainian prosecutor fired. It turns out that prosecutor was investigating that same oil company that was paying his son and shelling out hundreds of thousands of dollars every month to Hunter Biden's U.S. firm.

(The May 27 episode was a “Best of Hannity opening monologues” show, according to Nexis.)