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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 addReference(self, reference):
 """ Adds the specified reference to this ReferenceSet. """

        id_ = reference.getId()
        self._referenceIdMap[id_] = reference
        self._referenceNameMap[reference.getLocalId()] = reference
        self._referenceIds.append(id_)