# Description

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A recent PR
(https://github.com/isaac-sim/IsaacLab/pull/1530#issuecomment-2558120594)
causes issues with joint_parameter_lookup attributes of Articulation
Configs. The `class_to_dict` utility function needs to return a
primitive dict. Returning a torch.Tensor conflicts with OmegaConf.

This PR adds a unittest for the dict conversion as requested by @lgulich
so that the issue can be fixed. The test case fails on main branch as
expected according to my understanding. Passes on v1.3.0.

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## Type of change

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- Breaking change (fix or feature that would cause existing
functionality to not work as expected)

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## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [ ] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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