import pygame

window = pygame.display.set_mode((600, 600))
pygame.display.set_caption("ASSHOLE!")
screen = pygame.Surface((600, 600))
screen.fill((50,50,50))

class Sprite:
    def __init__(self, xpos, ypos, filename):
        self.x=xpos
        self.y=ypos
        self.bitmap=pygame.image.load(filename)
        self.bitmap.set_colorkey((0,0,0))
    def render(self):
        screen.blit(self.bitmap, (self.x,self.y))

laser = Sprite(0, 0, 'laser.png')

done = True
while done:
    for e in pygame.event.get():
        if e.type == pygame.QUIT:
            done = False

screen.fill((50,50,50))

laser.render()
window.blit(screen, (0,0))

window.blit(screen, (0, 0))
pygame.display.flip()