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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_size(self, pt=None, px=None):
 """ Set the size of the font, in px or pt. The px method is a bit inacurate, there can be one or two px less, and max 4 for big numbers (like 503) but the size is never over-estimated. It makes almost the good value. """


        assert (pt, px) != (None, None)

        if pt is not None:
            self.__init__(pt, self.font_name)
        else:
            self.__init__(self.px_to_pt(px), self.font_name)