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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 conversion_rate(self):
 """ The percentage of participants that have converted for this variant. Returns a > 0 float representing a percentage rate. """

        participants = self.participant_count
        if participants == 0:
            return 0.0
        return self.experiment.conversions_for(self.name) / float(participants)