python以及pygame遇到类的问题

main.py

from source import tools

def main():
game = tools.Game()
game.run()

if name == 'main':
main()

tools.py

import pygame
from source import constants as cnt

class Game(object):

def __int__(self):
    pygame.init()
    pygame.display.set_mode((cnt.SCREEN_W, cnt.SCREEN_H))
    self.screen = pygame.display.get_surface()
    self.clock = pygame.time.Clock()

def run(self):
    while True:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                exit()
            elif event.type == pygame.KEYDOWN:
                self.keys = pygame.key.get_pressed()
            elif event.type == pygame.KEYUP:
                self.keys = pygame.key.get_pressed()
        self.screen.fill((255, 255, 255))
        pygame.display.update()
        self.clock.tick(60)

error

pygame.error: video system not initialized

img