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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 get(self, model, **spec):
 """get a single model instance by handle :param model: model :param handle: instance handle :return: """


        handles = self.__find_handles(model, **spec)
        if len(handles) > 1:
            raise MultipleObjectsReturned()
        if not handles:
            raise ObjectDoesNotExist()
        return self.get_instance(model, handles[0])