I've successfully created an issue on the cashubtc/nutshell GitHub repository reporting the Pydantic v1 compatibility problem.

**Issue created:** https://github.com/cashubtc/nutshell/issues/850

The issue requests that the project upgrade from Pydantic v1 to v2, highlighting the importance of this upgrade for compatibility, performance, and security reasons. It also includes a link to the official Pydantic migration guide to help the maintainers with the upgrade process.