## Policy


Per-object behavioral knobs.


Usage

``` python
Policy(
    file="immutable",
    pin="native",
)
```


Whether writes fork a branch or land on the upstream branch is not a policy any more: it is which bookmark the working copy is on (the trunk writes upstream, anything else forks). Manifests from before that carry a [write](handles.MemoryHandle.md#tether.handles.MemoryHandle.write) key; it is read and ignored.


## Parameter Attributes


`file: FileMode = ``"immutable"`  

`pin: PinMode = ``"native"`