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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 colorspace(im, bw=False, replace_alpha=False, **kwargs):
 """ Convert images to the correct color space. A passive option (i.e. always processed) of this method is that all images (unless grayscale) are converted to RGB colorspace. This processor should be listed before :func:`scale_and_crop` so palette is changed before the image is resized. bw Make the thumbnail grayscale (not really just black & white). replace_alpha Replace any transparency layer with a solid color. For example, ``replace_alpha='#fff'`` would replace the transparency layer with white. """

    if im.mode == 'I':
        # PIL (and pillow) have can't convert 16 bit grayscale images to lower
        # modes, so manually convert them to an 8 bit grayscale.
        im = im.point(list(_points_table()), 'L')

    is_transparent = utils.is_transparent(im)
    is_grayscale = im.mode in ('L', 'LA')
    new_mode = im.mode
    if is_grayscale or bw:
        new_mode = 'L'
    else:
        new_mode = 'RGB'

    if is_transparent:
        if replace_alpha:
            if im.mode != 'RGBA':
                im = im.convert('RGBA')
            base = Image.new('RGBA', im.size, replace_alpha)
            base.paste(im, mask=im)
            im = base
        else:
            new_mode = new_mode + 'A'

    if im.mode != new_mode:
        im = im.convert(new_mode)

    return im