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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 rgb(self):
 """ An |RGBColor| value or |None| if no RGB color is specified. When :attr:`type` is `MSO_COLOR_TYPE.RGB`, the value of this property will always be an |RGBColor| value. It may also be an |RGBColor| value if :attr:`type` is `MSO_COLOR_TYPE.THEME`, as Word writes the current value of a theme color when one is assigned. In that case, the RGB value should be interpreted as no more than a good guess however, as the theme color takes precedence at rendering time. Its value is |None| whenever :attr:`type` is either |None| or `MSO_COLOR_TYPE.AUTO`. Assigning an |RGBColor| value causes :attr:`type` to become `MSO_COLOR_TYPE.RGB` and any theme color is removed. Assigning |None| causes any color to be removed such that the effective color is inherited from the style hierarchy. """

        color = self._color
        if color is None:
            return None
        if color.val == ST_HexColorAuto.AUTO:
            return None
        return color.val