For just a score variable, it's probably not a big deal to have an = 0 in there twice as duplicate code, but games are complicated and so I'm sure you've got lots of other fields as well, and that's where the duplication becomes problematic, especially if it's just there to appease the linter. I'm assuming the Game object is sort of an application context that survives the entire duration of the program's runtime, and that aside from score, you have a variety of other fields as well that need to be reset. For things like this, I would split game into a 2-tiered object, where each object has the desired lifespan. Something like this...
class ApplicationContext:
def __init__(self):
self.session = GameSession()
def reset(self):
self.session = GameSession()
def __init__(self):
self.score = 0
self.player_location = (0, 0)
self.zombies = self.build_zombie_list()
self.im_just_making_up_examples = etc
Nope, this doesn't solve your fundamental problem of getting rid of a duplicate assignment, but it does group things with identical lifecycles so that the duplication is always limited to just the single 'session' field no matter how complicated your game becomes.