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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 create_color_scheme(background=None, foreground=None, error=None, custom=None, red=None, green=None, yellow=None, blue=None, magenta=None, cyan=None):
 """ Utility function that creates a color scheme instance, with default values. The default colors are chosen based on the current palette. :param background: background color :param foreground: foreground color :param error: color of error messages (stderr) :param custom: color of custom messages (e.g. to print the full command or the process exit code) :param red: value of the red ANSI color :param green: value of the green ANSI color :param yellow: value of the yellow ANSI color :param blue: value of the blue ANSI color :param magenta: value of the magenta ANSI color :param cyan: value of the cyan ANSI color :return: A ColorScheme instance. """

        if background is None:
            background = qApp.palette().base().color()
        if foreground is None:
            foreground = qApp.palette().text().color()
        is_light = background.lightness() >= 128
        if error is None:
            if is_light:
                error = QColor('dark red')
            else:
                error = QColor('#FF5555')
        if red is None:
            red = QColor(error)
        if green is None:
            if is_light:
                green = QColor('dark green')
            else:
                green = QColor('#55FF55')
        if yellow is None:
            if is_light:
                yellow = QColor('#aaaa00')
            else:
                yellow = QColor('#FFFF55')
        if blue is None:
            if is_light:
                blue = QColor('dark blue')
            else:
                blue = QColor('#5555FF')
        if magenta is None:
            if is_light:
                magenta = QColor('dark magenta')
            else:
                magenta = QColor('#FF55FF')
        if cyan is None:
            if is_light:
                cyan = QColor('dark cyan')
            else:
                cyan = QColor('#55FFFF')
        if custom is None:
            custom = QColor('orange')
        return OutputWindow.ColorScheme(background, foreground, error, custom,
                                        red, green, yellow, blue, magenta, cyan)