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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 _read_models(self, graph):
 """ Read graph and add models to document """

        for e in self._get_elements(graph, SBOL.Model):
            identity = e[0]
            m = self._get_rdf_identified(graph, identity)
            m['source'] = self._get_triplet_value(graph, identity, SBOL.source)
            m['language'] = self._get_triplet_value(graph, identity, SBOL.language)
            m['framework'] = self._get_triplet_value(graph, identity, SBOL.framework)
            obj = Model(**m)
            self._models[identity.toPython()] = obj
            self._collection_store[identity.toPython()] = obj