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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 evaluation(self, evl):
 """ Sets the statistic to use for evaluation. :param evl: the statistic :type evl: SelectedTag, Tag or str """

        if isinstance(evl, str):
            evl = self.tags_evaluation.find(evl)
        if isinstance(evl, Tag):
            evl = SelectedTag(tag_id=evl.ident, tags=self.tags_evaluation)
        javabridge.call(self.jobject, "setEvaluation", "(Lweka/core/SelectedTag;)V", evl.jobject)