def groups(self):
        return set(opt.group_name for opt in self._options.values())
Ensure that a document superclass can be marked as abstract
dataset/ETHPy150Open D-L/SimpleBookMarks/src/tornado/options.py/OptionParser.groups--crossover with--dataset/ETHPy150Open MongoEngine/mongoengine/tests/document/inheritance.py/InheritanceTest.test_abstract_documents