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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 crpss(self):
 """ Calculate the continous ranked probability skill score from existing data. """

        crps_f = self.crps()
        crps_c = self.crps_climo()
        return 1.0 - float(crps_f) / float(crps_c)