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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 generate_thresholdcurve_data(evaluation, class_index):
 """ Generates the threshold curve data from the evaluation object's predictions. :param evaluation: the evaluation to obtain the predictions from :type evaluation: Evaluation :param class_index: the 0-based index of the class-label to create the plot for :type class_index: int :return: the generated threshold curve data :rtype: Instances """

    jtc = JavaObject.new_instance("weka.classifiers.evaluation.ThresholdCurve")
    pred = javabridge.call(evaluation.jobject, "predictions", "()Ljava/util/ArrayList;")
    result = Instances(
        javabridge.call(jtc, "getCurve", "(Ljava/util/ArrayList;I)Lweka/core/Instances;", pred, class_index))
    return result