A pint-sized gangbanger who allegedly sparked a bloody turf war that left three people dead in one night was sentenced Friday — and brazenly told a pal in the courtroom to go “smoke that weed!” as he was hauled off to prison.Up The Hill gang member Zymir Humphrey, 20, was sentenced to 15-years-to-life behind bars by Manhattan Supreme Court Judge Abraham Clott after copping to the 2022 murder of 21-year-old Brandon Atkinson in Alphabet City.Humphrey’s fatal shooting of Atkinson, an associate of rival Down The Hill gang, led to the grisly killings of innocent college basketball player Jesse Parrilla and his gal pal Nikki Huang, authorities said.During the sentencing hearing, Humphrey, who pleaded guilty to second-degree murder, showed no remorse for gunning down Atkinson.Humphrey did give a short apology to the families of Parrilla and Huang, who were found shot to death and torched inside a car at a Bronx park due because his gang hit.“I would like to apologize to Nikki Huang’s family because in all reality she had nothing to do with this situation, and Jesse’s family also.Other than that…,” he said, while shaking his head.Instead, Humphrey took his final moments before being transferred to an upstate prison to chum it up with a pal in the courtroom, yelling at him, “Yo, smoke that weed!” before being shuffled out in handcuffs.Manhattan Assistant District Attorney Andrew Mercer said Humphrey was the catalyst for a “gang war” that broke out on the the Lower East Side after he sought out a rival gang member for mugging Huang and snatching her handbag.Humphrey went into rival territory and shot Atkinson in the back of the head near East 3rd Street and Avenue D on May 15, 2022, prosecutors said.But Atkinson had nothing to do with the robbery of Huang’s handbag, the DA’s Office said.Members of the Down the Hill gang then kidnapped Huang while she was hanging out with Parrilla, a onetime hoopster at Genesee Community College, authorities said...