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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_enrichment(self):
 """Mark as 'enriched' or 'purified'."""

        if self.study_n:
            return 'e' if ((1.0 * self.study_count / self.study_n) >
                           (1.0 * self.pop_count / self.pop_n)) else 'p'
        return 'p'