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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 _get_image_size(self, maxcharno, maxlineno):
 """ Get the required image size. """

        return (self._get_char_x(maxcharno) + self.image_pad,
                self._get_line_y(maxlineno + 0) + self.image_pad)