Python精灵模块的addpopup指令

from sprites import Screen,Sprite,Mouse

screen = Screen()
screen.setup(480,360)
screen.bgpic('res/sky.png')
screen.addpopup()         # 单击右键可显示右键菜单

bug = Sprite()
leftkey = Mouse()         # 实例化鼠标左键

# 单击左键并松开后,再单击右键则显示不了右键菜单了
while not leftkey.downup():screen.update()
screen.removepopup()     # 移去右键菜单

screen.mainloop()