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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 register_model(self, model, bundle):
 """ Registers a bundle as the main bundle for a model. Used when we need to lookup urls by a model. """

        if model in self._model_registry:
            raise AlreadyRegistered('The model %s is already registered' \
                                     % model)

        if bundle.url_params:
            raise Exception("A primary model bundle cannot have dynamic \
                            url_parameters")

        self._model_registry[model] = bundle