python 跟着鼠标走的火柴人

import pygame


black = (0,0,0)
white = (255,255,255)
red = (255,0,0)
green = (0,255,0)

def draw_a_boy(screen,x,y):
    pygame.draw.ellipse(screen,black,[x,y-5,10,10])
    pygame.draw.line(screen,red,[5+x,5+y],[5+x,15+y],2)
    pygame.draw.line(screen,red,[5+x,5+y],[x-5,15+y],2)
    pygame.draw.line(screen,red,[5+x,5+y],[15+x,15+y],2)
    pygame.draw.line(screen,black,[5+x,15+y],[x-5,25+y],2)
    pygame.draw.line(screen,black,[5+x,15+y],[15+x,25+y],2)




pygame.init()
size = (700,500)
screen = pygame.display.set_mode(size)
pygame.display.set_caption("a boy")


done = False
clock = pygame.time.Clock()
x=15
y=15

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

    pos = pygame.mouse.get_pos()
    x = pos[0]
    y = pos[1]

    pygame.mouse.set_visible(False)
    

    screen.fill(white)
    draw_a_boy(screen,x,y)

   
    clock.tick(20)
    pygame.display.flip()

pygame.quit()