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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 refresh(self) -> None: """Prepare the actual |anntools.SeasonalANN| object for calculations. Dispite all automated refreshings explained in the general documentation on class |anntools.SeasonalANN|, it is still possible to destroy the inner consistency of a |anntools.SeasonalANN| instance, as it stores its |anntools.ANN| objects by reference. This is shown by the following example: (2, 3) (1, 1) Due to the C level implementation of the mathematical core of both |anntools.ANN| and |anntools.SeasonalANN| in module |annutils|, such an inconsistency might result in a program crash without any informative error message. Whenever you are afraid some inconsistency might have crept in, and you want to repair it, call method |anntools.SeasonalANN.refresh| explicitly: (2, 3) (2, 3) """

        # pylint: disable=unsupported-assignment-operation
        if self._do_refresh:
            if self.anns:
                self.__sann = annutils.SeasonalANN(self.anns)
                setattr(self.fastaccess, self.name, self._sann)
                self._set_shape((None, self._sann.nmb_anns))
                if self._sann.nmb_anns > 1:
                    self._interp()
                else:
                    self._sann.ratios[:, 0] = 1.
                self.verify()
            else:
                self.__sann = None