swh_storage = <swh.storage.in_memory.InMemoryStorage object at 0x7f386bf8c550> def test_snapshot_resolve_aliases_no_aliases(swh_storage): snapshot = Snapshot(branches={}) > swh_storage.snapshot_add([snapshot]) .tox/py3/lib/python3.7/site-packages/swh/storage/tests/algos/test_snapshot.py:288: _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ self = <swh.storage.in_memory.InMemoryStorage object at 0x7f386bf8c550> snapshots = [Snapshot(branches=ImmutableDict({}), id=b'\x1a\x88\x93\xe6\xa8oDN\x8b\xe8\xe7\xbd\xa6\xcb4\xfb\x175\xa0\x0e')] def snapshot_add(self, snapshots: List[Snapshot]) -> Dict: > if not self._allow_overwrite: E AttributeError: 'InMemoryStorage' object has no attribute '_allow_overwrite' .tox/py3/lib/python3.7/site-packages/swh/storage/cassandra/storage.py:668: AttributeError