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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 update(self, forecasts, observations):
 """ Update the statistics with a set of forecasts and observations. Args: forecasts (numpy.ndarray):
 Array of forecast probability values observations (numpy.ndarray):
 Array of observation values """

        for t, threshold in enumerate(self.thresholds[:-1]):
            self.frequencies.loc[t, "Positive_Freq"] += np.count_nonzero((threshold <= forecasts) &
                                                                         (forecasts < self.thresholds[t+1]) &
                                                                         (observations >= self.obs_threshold))
            self.frequencies.loc[t, "Total_Freq"] += np.count_nonzero((threshold <= forecasts) &
                                                                      (forecasts < self.thresholds[t+1]))