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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 _update_info(self):
 """ Update metadata for this HDU """

        try:
            self._FITS.movabs_hdu(self._ext+1)
        except IOError:
            raise RuntimeError("no such hdu")

        self._info = self._FITS.get_hdu_info(self._ext+1)