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Here's How Kanye West Turned A Paul McCartney Sketch Into 'All Day'

Sir Paul walks us through their creative process

Though none of the songs made the final The Life of Pablo tracklist, 2015's trio of Kanye West and Paul McCartney collaborations -- "Only One," "FourFiveSeconds" and "All Day" -- showed the potential of the unlikely pairing.

"I love Kanye," McCartney told John Wilson on BBC Radio 4's Mastertapes on Tuesday. "People say he's eccentric, which you'd have to agree with. He's a monster. He's a crazy guy that comes up with great stuff. He inspires me."

From there, he walked through his initial hesitancy when he heard 'Ye wanted to work with him, as well as their writing and collaborative process. Often what happened, it seems, is that they'd jam and vibe out in the studio, and Kanye would tweak Sir Paul's contributions for the final versions.

"I whistled the melody," he said, explaining that he was trying to play a chord with just two fingers, after being inspired by a Picasso painting. "I was telling that to Kanye, and he went, ‘Oh, yeah. Great, man.' He didn't appear to really notice. And then, after Christmas, I get this track back. He's taken my melody, and he's made it seriously urban. And that was a thing called ‘All Day.’"

Quite a thing it was.