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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 add_supporting_evidence(self, evidence_line, evidence_type=None, label=None):
 """ Add supporting line of evidence node to association id :param evidence_line: curie or iri, evidence line :param evidence_type: curie or iri, evidence type if available :return: None """

        self.graph.addTriple(
            self.association, self.globaltt['has_supporting_evidence_line'],
            evidence_line)
        if  evidence_type is not None:
            self.model.addIndividualToGraph(evidence_line, label, evidence_type)
        return