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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_models(self):
 """ Get a list of content models the object subscribes to. """

        try:
            rels = self.rels_ext.content
        except RequestFailed:
            # if rels-ext can't be retrieved, confirm this object does not have a RELS-EXT
            # (in which case, it does not have any content models)
            if "RELS-EXT" not in self.ds_list.keys():
                return []
            else:
                raise

        return list(rels.objects(self.uriref, modelns.hasModel))