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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_closest(self, sma):
 """ Return the `~photutils.isophote.Isophote` instance that has the closest semimajor axis length to the input semimajor axis. Parameters sma : float The semimajor axis length. Returns ------- isophote : `~photutils.isophote.Isophote` instance The isophote with the closest semimajor axis value. """


        index = (np.abs(self.sma - sma)).argmin()
        return self._list[index]