@webhook_endpoint
async def trigger_training(payload: WebhookPayload) -> None:
if payload.repo.type == "dataset" and payload.event.action == "update":
# Trigger a training job if a dataset is updated
...
```  
Save this snippet in a file called `'app.py'` and run it with `'python app.py'`. You should see a message like this:  
```text
Webhook secret is not defined. This means your webhook endpoints will be open to everyone.