Manage model stage

This example assumes using tags to indicate model stage.

To change the model stage:

Initialize the run representing the model:
```
import neptune

run = neptune.init_run(with_id="CLS-56")
```
How do I find the ID?

The Neptune ID is a unique identifier for the run. The Experiments tab displays it in the leftmost column.

In the run structure, the ID is stored in the system namespace (sys).
- If the run is active, you can obtain its ID with run["sys/id"].fetch(). For example:
```
>>> run = neptune.init_run()
...
>>> run["sys/id"].fetch()
'CLS-26'
```
- If you set a custom run ID, it's stored at sys/custom_run_id:
```
>>> run["sys/custom_run_id"].fetch()
'vigilant-puffin-20bt9'
```
Delete the tag for the previous stage:
```
run["sys/tags"].remove("development")
```
Add the tag for the new stage:
```
run["sys/tags"].add("production")
```
To stop the connection to Neptune and sync all data, call the stop() method:
```
run.stop()
```

See in Neptune See example code on GitHub

Conditionally changing the stage#

You can make the stage transition conditional by fetching the relevant metadata from the run and checking the value.

The following code snippet fetches an accuracy value from the logged metrics, then compares it against a threshold of 0.9 before making the change:

run = neptune.init_run(
    with_id="CLS-56",
    capture_hardware_metrics=False,
    capture_stderr=False,
    capture_stdout=False,
    capture_traceback=False,
    git_ref=False,
    source_code=[],
)

val_acc = run["validation/acc"].fetch()

if val_acc <= 0.7:
    run["sys/tags"].remove("development")
    run["sys/tags"].add("archived")