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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 get_analysis_type(self, instance):
 """Returns the string used in slots to differentiate amongst analysis types """

        if IDuplicateAnalysis.providedBy(instance):
            return 'd'
        elif IReferenceAnalysis.providedBy(instance):
            return instance.getReferenceType()
        elif IRoutineAnalysis.providedBy(instance):
            return 'a'
        return None