.github/PULL_REQUEST_TEMPLATE.md

## 📝 Summary

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Provide a concise summary of what this pull request is addressing.

Link to the issue in which this notebook or course was proposed.
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## 📋 Checklist

- [ ] I have included package dependencies in the notebook file [using `--sandbox`](https://docs.marimo.io/guides/package_reproducibility/)
- [ ] If adding a course, include a `README.md`
- [ ] Keep language direct and simple.