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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 max_csi(self):
 """ Calculate the maximum Critical Success Index across all probability thresholds Returns: The maximum CSI as a float """

        csi = self.contingency_tables["TP"] / (self.contingency_tables["TP"] + self.contingency_tables["FN"] +
                                               self.contingency_tables["FP"])
        return csi.max()