You’d think if late rapper/actor Tupac Shakur were going to come back to life and attend an NBA game, it would be a Knicks or Lakers game, since he lived his adult life in New York and Los Angeles. But Wednesday night at TD Garden, a gentleman who looked a whole lot like Tupac — down to the mustache, goatee, and tied bandana — spent the evening enjoying a Celtics game. The unidentified Tupac doppelganger seemed to enjoy the attention, waving to the crowd, posing for pictures, and smiling as fans who had given up on the game (the C’s lost big to Golden State) began chanting “Let’s go, Tupac!” He even showed a few dance moves for the Jumbotron when the DJ began playing Pac’s 1996 hit, “California Love.” “He’s been to games before, going back to 2007,” said Celtics spokeswoman Heather Walker. “It was just a really funny, organic moment.”James Burnett can be reached at firstname.lastname@example.org. Follow him on Twitter @JamesBurnett.