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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_parameters(self, graph=None):
 """Return the model parameters in the form of numpy arrays. :param graph: tf graph object :return: model parameters """

        g = graph if graph is not None else self.tf_graph

        with g.as_default():
            with tf.Session() as self.tf_session:
                self.tf_saver.restore(self.tf_session, self.model_path)

                return {
                    'W': self.W.eval(),
                    'bh_': self.bh_.eval(),
                    'bv_': self.bv_.eval()
                }