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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 clearCanvas(self, fillColor = 0 ):
 """! \~engliash Clear up canvas and fill color at same time @param fillColor: a color value @note The fillColor value range depends on the setting of _buffer_color_mode. * If it is SS_COLOR_MODE_MONO ("1") monochrome mode, it can only select 0: black and 1: white * If it is SS_COLOR_MODE_RGB ("RGB") color mode, RGB color values can be used \~chinese 清除画布并同时填充颜色 @param fillColor: 颜色值 @note fillColor 取值范围取决于 _buffer_color_mode 的设定。 * 如果是 SS_COLOR_MODE_MONO ("1") 单色模式，只能选择 0:黑色 和 1:白色 * 如果是 SS_COLOR_MODE_RGB ("RGB") 彩色模式，可以使用 RGB 色彩值 """

        self.Canvas.rectangle((0, 0, self._display_size[0], self._display_size[1]), outline=0, fill=fillColor)