[Python] Advice on Mixture of Singleton and State Design Pattern in Python

in pygame, i'm making a game and as far as i know, nobody creates two instances of a game (justifies Singleton), and my game has different states like "start menu", "game over", "playing" (Justifies State Design Pattern)

at First i wanted to force the States to be Singleton but i realized i might add states later down the road that need different variables, so this came to my mind:

class GameState(ABC):

@abstractmethod
def exit(self):
pass


and this is my GameMeta

class GameMeta(type):
_instances = {}

def __call__(cls):
if cls not in cls._instances:
instance = super().__call__()
cls._instances[cls] = instance
return cls._instances[cls]


, i have

class StartMenu(GameState):
def exit(self):
pass


as a game state, i also have "GameOver" and "Playing" classes similar to "StartMenu", and in my main.py i have Game, it starts the game instance:

class Game(metaclass=GameMeta):
def __init__(self):
self.current_state: GameState = StartMenu()
self.screen = None


, is there any sign of bad practice? i'm mixing Singleton and State Pattern, Any Mistakes? or Violation of Design Pattern or Principle? is this a bad idea altogether?

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