def keys(self):
        return map(self._decode, os.listdir(self.dname))
helper function for __init__:
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/persisted/dirdbm.py/DirDBM.keys--crossover with--dataset/ETHPy150Open chrisglass/django_polymorphic/polymorphic/models.py/PolymorphicModel._get_inheritance_relation_fields_and_models