python - 嵌套的defs不起作用

Question

我需要在第二个 def 语句中添加什么才能使其正常工作？

def main():
    # the user has to choose a picture and then he is asked to
    pic = makePicture(pickAFile())

    # the user is asked to select a color that he wants to remove from a picture
    color = requestString("Which color would you like to remove?")
    show(pic)

    # whats wrong with this last part that doesn't make the modifications to the picture
    def RemoveColor(pic, color):
        r = red
        g = green
        b = blue
        for px in getPixels(pic):
            setRed(px, 0)

        for px in getPixels(pic):
            setGreen(px, 0)

        for px in getPixels(pic):
            setBlue(px, 0)

    repaint(pic)

Answer 1

RemoveColor在这里我从你的函数中取出函数main，然后从内部调用它main

def RemoveColor(pic, color):
    r = red
    g = green
    b = blue
    for px in getPixels(pic):
        setRed(px, 0)

    for px in getPixels(pic):
        setGreen(px, 0)

    for px in getPixels(pic):
        setBlue(px, 0)

def main():
    # the user has to choose a picture and then he is asked to
    pic = makePicture(pickAFile())

    # the user is asked to select a color that he wants to remove from a picture
    color = requestString("Which color would you like to remove?")
    show(pic)

    RemoveColor(pic, color) # HERE I'M CALLING RemoveColor
    repaint(pic)