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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 _change_soi(self, body):
 """Modify the inner parameters of the Kepler propagator in order to place the spacecraft in the right Sphere of Influence """


        if body == self.central:
            self.bodies = [self.central]
            self.step = self.central_step
            self.active = self.central.name
            self.frame = self.central.name
        else:
            soi = self.SOI[body.name]
            self.bodies = [body]
            self.step = self.alt_step
            self.active = body.name
            self.frame = soi.frame