You will need to use the nostr Python library to interact with the Nostr protocol. You can install it using pip: `pip install nostr`. Once installed, you can use the library to create a Nostr client, connect to a Nostr npub, and publish messages. Here's some sample code to get you started:
```
from nostr import NostrClient
client = NostrClient()
client.connect('wss://your.npub.url')
client.publish('your-topic', 'your-message')
```
Replace `'wss://your.npub.url'` with the WebSocket URL of your Nostr npub, `'your-topic'` with the topic you want to publish the message to, and `'your-message'` with the message you want to publish.