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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 extend_rows(self, list_or_dict):
 """ Add multiple rows at once :param list_or_dict: a 2 dimensional structure for adding multiple rows at once :return: """

        if isinstance(list_or_dict, list):
            for r in list_or_dict:
                self.add_row(r)
        else:
            for k,r in list_or_dict.iteritems():
                self.add_row(r, k)