Filmmaker Vikram Gandhi's 'Barry' tells the story of a young man with an absent father struggling to find his identity in a big city. It is also the tale of an individual who would decades later become US President Barack Obama.

The film, which had its world premiere at the Toronto International Film Festival on Saturday, is set in 1981 and draws on Obama's memoir, "Dreams From My Father," to frame his formative years.

But it also takes creative license with the story, with love interest Charlotte (Anya Taylor-Joy) an amalgam of three white girlfriends from his time studying at Columbia University in New York City.

The 20-year-old future president, played by Devon Terrell, makes friends easily but feels as out of place when Charlotte takes him to meet her parents at a country club as when he joins his basketball buddy at a party in a Harlem housing project.

"Because this man is such a charismatic, celebrated person, I think it's important to see that he was once struggling with the same identity issues as so many other people," Gandhi, who also studied at Columbia, said in an interview.

Months away from the election to choose Obama's replacement in the White House, Gandhi said the film feeds into an early-onset nostalgia for what the first US president of colour represents.

"He's not even out of office but we miss already what Obama stands for," he said, contrasting that with the campaign of Republican candidate Donald Trump.

"There's something incredibly decent and humble in Barack Obama and I find that Donald Trump is preying on the darkest parts of our psyche," he said.

For Terrell, himself of mixed race, the tale of Obama's early years goes beyond race.

"I think everyone in life, no matter race or religion, we try to find a place to put ourselves," said the US-born actor who grew up in Australia.

In his film debut, the 23-year-old has won plaudits for his command of Obama's mannerisms, the early versions of his measured responses to discord and debate.

"Terrell nails the clipped vibe of awareness, and a youthful version of the stare, to an uncanny degree," Variety wrote in a review of the film.

'Barry' does not yet have a US distributor. It will be released in Canada by Elevation Pictures.