第 11 步：这条线的斜率是多少？让我们问问用户！我们将不得不使用点符号。
- 在找到Ask for Float块并将其拖到代码编辑器中。
- 将括号中的字符串更改为"What is the slope of this line?"
- 将变量（等号左侧的单词）从guess更改为slopeguess 。
- 找到命令中显示sprite .ask的部分并将其更改为line .ask() 。
To navigate the page using the TAB key, first press ESC to exit the code editor.
stage.set_axis(100)
stage.create_grid_overlay(10, "grey")
stage.set_background("soccerfield")
ballx = -80
bally = random.randint(-100,100)
# sprite = codesters.Sprite("image", x, y)
ball = codesters.Sprite("soccerball", ballx, bally)
netx = 90
nety = random.randint(-100,100)
# sprite = codesters.Sprite("image", x, y)
net = codesters.Sprite("soccernet", netx, nety)
net.flip_right_left()
#sprite = codesters.Line(x-start, y-start, x-end, y-end, "color")
line = codesters.Line(ballx, bally, netx, nety, "blue")
