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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 doc(self, export='plain'):
 """ Dump help document for setting classes """

        rows = []
        title = '<{:s}> config options'.format(self.__class__.__name__)
        table = Tab(export=export, title=title)

        for opt in sorted(self.config_descr):
            if hasattr(self, opt):
                c1 = opt
                c2 = self.config_descr[opt]
                c3 = self.__dict__.get(opt, '')
                c4 = self.get_alt(opt)
                rows.append([c1, c2, c3, c4])
            else:
                print('Setting {:s} has no {:s} option. Correct in config_descr.'.
                      format(self.__class__.__name__, opt))

        table.add_rows(rows, header=False)
        table.header(['Option', 'Description', 'Value', 'Alt.'])

        return table.draw()