## testing.Pin


A durable native reference created for a committed state.


Usage

``` python
testing.Pin(
    id,
    ref,
    created=True,
)
```


## Parameter Attributes


`id: str`  

`ref: str`  

`created: bool = ``True`  
Whether this [pin()](testing.ObjectBackend.md#tether.testing.ObjectBackend.pin) call created the ref (`False`: it already carried the state). Runtime only - not serialised. The engine rolls back only the pins it created; a reused pin belongs to the commit that made it.