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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 instance_throughput_ratio(self, inst_id):
 """ The relative throughput of an instance compared to the backup instances. """

        inst_thrp, otherThrp = self.getThroughputs(inst_id)

        # Backup throughput may be 0 so moving ahead only if it is not 0
        r = inst_thrp / otherThrp if otherThrp and inst_thrp is not None \
            else None
        return r