Letterman regrets retirement now that Trump is running for president

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Funnyman David Letterman reveals he may have retired too early.

The former “Late Show” host came out of retirement for one night to give his Top 10 list on plainspoken, billionaire investor and television personality, who as of last month can add 2016 GOP presidential candidate to his long list of titles.

“I was complacent, I was satisfied, I was content, and then a couple of days ago Donald Trump said he was running for president. I’ve made the biggest mistake of my life ladies and gentleman,” Letterman joked.

The Donald Trump-themed Top 10 list was revealed during a surprise appearance on Martin Short and Steve Martin's A Very Stupid Conversation show in San Antonio, Texas, on Friday.

Letterman jokingly said that the "thing" on his head was the gopher in the movie Caddyshack, and he predicted Trump says his own name during sex.

Watch the video for the full list.