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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 accuracy(mod_y, ref_y, summary=True, name="accuracy"):
 """Accuracy computation op. Parameters mod_y : tf.Tensor Model output tensor. ref_y : tf.Tensor Reference input tensor. summary : bool, optional (default = True) Whether to save tf summary for the op. Returns ------- tf.Tensor : accuracy op. tensor """

        with tf.name_scope(name):
            mod_pred = tf.argmax(mod_y, 1)
            correct_pred = tf.equal(mod_pred, tf.argmax(ref_y, 1))
            accuracy = tf.reduce_mean(tf.cast(correct_pred, tf.float32))
            if summary:
                tf.summary.scalar('accuracy', accuracy)
            return accuracy