Update test_alerts.py

[zjt-code]

add example code

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Description

Motivation and Context

Types of changes

• Change to the site (I have double-checked the Netlify deployment, and my changes look good)
• Code example added (and I also added the example to all translated languages)
• Improved translation
• Added new translation (and I also added a notice to each document missing translation)

Checklist

• I have read the contributing document.
• I have used hugo to render the site/docs locally and I am sure it works.

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[diemol]

Can you share the page where this example would be used? Then we can link it and show it in the docs.