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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_owner(self, new_owner):
 """ Changes ownership of an organization. """

        old_owner = self.owner.organization_user
        self.owner.organization_user = new_owner
        self.owner.save()

        # Owner changed signal
        owner_changed.send(sender=self, old=old_owner, new=new_owner)