def test_readonly(self):
        try:
            self.db.copy()              # what should 'copy' do on AD?
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
        try:                           # what should 'setdefault' do on AD?
            self.db.setdefault('foo')
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
        try:                           # what should 'update' do on AD?
            self.db.update({})
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
        try:
            self.db.clear()
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
        try:
            self.db.pop()
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
        try:
            self.db.popitem()
            assert 0, 'this method should raise NotImplementedError'
        except NotImplementedError:
            pass
A newly created filesystem is empty after being mounted.
dataset/ETHPy150Open cjlee112/pygr/tests/annotation_test.py/AnnotationDB_Test.test_readonly--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/agents/test/test_blockdevice.py/MountBlockDeviceTests.test_new_is_empty