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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 bounding_ellipses(self):
 """ Compute the semimajor axis of the two ellipses that bound the annulus where integrations take place. Returns ------- sma1, sma2 : float The smaller and larger values of semimajor axis length that define the annulus bounding ellipses. """


        if (self.linear_growth):
            a1 = self.sma - self.astep / 2.
            a2 = self.sma + self.astep / 2.
        else:
            a1 = self.sma * (1. - self.astep / 2.)
            a2 = self.sma * (1. + self.astep / 2.)

        return a1, a2