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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 set_border(self, thickness, color="black"):
 """ Sets the border thickness and color. :param int thickness: The thickenss of the border. :param str color: The color of the border. """

        self._set_tk_config("highlightthickness", thickness)
        self._set_tk_config("highlightbackground", utils.convert_color(color))