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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def color_replace(image, color):
 """Replace black with other color :color: custom color (r,g,b,a) :image: image to replace color :returns: TODO """

    pixels = image.load()
    size = image.size[0]
    for width in range(size):
        for height in range(size):
            r, g, b, a = pixels[width, height]
            if (r, g, b, a) == (0,0,0,255):
                pixels[width,height] = color
            else:
                pixels[width,height] = (r,g,b,color[3])