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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 init_serials(self, ses_seed):
 """ Generate unique seeds for each rupture with numpy.arange. This should be called only in event based calculators """

        sources = self.get_sources()
        serial = ses_seed
        for src in sources:
            nr = src.num_ruptures
            src.serial = serial
            serial += nr