'Unrescue the given instance.'

@check_instance_lock
@check_instance_state(vm_state=[vm_states.RESCUED])
def unrescue(self, context, instance):

    instance.task_state = task_states.UNRESCUING
    instance.save(expected_task_state=[None])
    self._record_action_start(context, instance, instance_actions.UNRESCUE)
    self.compute_rpcapi.unrescue_instance(context, instance=instance)
