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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 destroy(self):
 """ Remove this FirewallRule from the API. This instance must be associated with a server for this method to work, which is done by instantiating via server.get_firewall_rules(). """

        if not hasattr(self, 'server') or not self.server:
            raise Exception(
                """FirewallRule not associated with server;
                please use or server.get_firewall_rules() to get objects
                that are associated with a server.
                """)
        return self.server.cloud_manager.delete_firewall_rule(
            self.server.uuid,
            self.position
        )