def xyz_from_rgb(rgb):
    """Return an XYZ tuple converted from an RGB tuple."""
    return tuple([
        0.412453 * rgb[0] + 0.357580 * rgb[1] + 0.180423 * rgb[2],
        0.212671 * rgb[0] + 0.715160 * rgb[1] + 0.072169 * rgb[2],
        0.019334 * rgb[0] + 0.119193 * rgb[1] + 0.950227 * rgb[2]])