A COCKNEY STRAIGHT FROM HAMILTON

MARY’S new sidekick is Jack, who — instead of sweeping chimneys — lights London’s remaining gas lamps.

He is played by Lin-Manuel Miranda (right), best known for creating the hit stage musical Hamilton.

Puerto Rican Lin-Manuel, 38, says: ‘The [producers] told me: “If you want him to be an American, he can be.”

‘I said: “No, I’m trying my hand at the accent. We’re doing this. I don’t want to be in a Mary Poppins movie and not have a British accent.” ’

He says the multi-tasking involved was a challenge: ‘In one scene I light a lamp, ride a bike, steal an apple from a cart, throw it to an orphan child — all while singing in a Cockney accent.

‘That moment is the hardest ten seconds of my life!’