python.pygame中导入图片打不开原因

[weixin_45088152]

#_*_coding:utf-8_*_
import sys
import pygame

pygame.init()
size=width,height=640,480
screen=pygame.display.set_mode(size)
color=(0,0,0)

ball=pygame.image.load("ball.png")
ballrect=ball.get_rect()

while Ture:
for event in pygame.event.get():
if event.type==pygame.QUIT:
sys.exit()
screen.fill(color)
screen.blit(ball,ballrect)
pygame.display.flip()
pygame.quit()
错误编译：
Traceback (most recent call last):
File "C:\Program Files\Python37\ball\ball.py.py", line 10, in <module>
ball=pygame.image.load("ball.png")
pygame.error: Couldn't open ball.png

[萌新自学python中]

.png和.py放在同一级文件夹了吗？

[双双的爹]

当前文件夹应该用"./ball.png"