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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_rows(self):
 """ Returns the name of the rows of the extension"""

        possible_dataframes = ['F', 'FY', 'M', 'S',
                               'D_cba', 'D_pba',  'D_imp', 'D_exp',
                               'D_cba_reg', 'D_pba_reg',
                               'D_imp_reg', 'D_exp_reg',
                               'D_cba_cap', 'D_pba_cap',
                               'D_imp_cap', 'D_exp_cap', ]
        for df in possible_dataframes:
            if (df in self.__dict__) and (getattr(self, df) is not None):
                return getattr(self, df).index.get_values()
        else:
            logging.warn("No attributes available to get row names")
            return None