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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 value_matrix(self):
 """Converted rows of tabular data. Returns: |list| or |tuple|: Table rows. """


        if self.__value_matrix:
            return self.__value_matrix

        self.__value_matrix = [
            [value_dp.data for value_dp in value_dp_list] for value_dp_list in self.value_dp_matrix
        ]

        return self.__value_matrix