## upgrade.pending()


Migrations a dataset at [version](handles.DeltaHandle.md#tether.handles.DeltaHandle.version) still needs, oldest first.


Usage

``` python
upgrade.pending(version)
```


Every older format is brought to the current one by a single migration whose parts run on what the dataset *shows* (old-format pins, mtime file states, misplaced manifests, 0.1.0b3 identities), among the parts meant for datasets as old as it records.