## oplog.append_pinned()


Record `(pin id, kind, key)` triples this clone just created; a set, so


Usage

``` python
oplog.append_pinned(
    shared_dir,
    dataset_id,
    pins,
)
```


an id already on record is not written again. Creates the index when it is missing, even for no pins: its presence says it has been seeded.