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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [no-explicit-stacklevel
(B028)](https://docs.astral.sh/ruff/rules/no-explicit-stacklevel/#no-explicit-stacklevel-b028)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/1ee80aec-2d6e-4a3f-8e98-da82b6a9f544)
```py
warnings.warn("This is a warning")
```
[New example](https://play.ruff.rs/343593aa-38a0-4d76-a32b-5abd0a4306cc)
```py
import warnings
warnings.warn("This is a warning")
```
Imports were also added to the "use instead" section
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected
fde82fc563