# Description

Replaces import of 

```
try:
    import isaacsim.storage.native as nucleus_utils
except ModuleNotFoundError:
    import isaacsim.core.utils.nucleus as nucleus_utils
```

with own utils implemented inside the sim  utils folder.

```
import isaaclab.sim.utils.nucleus as nucleus_utils
```


## Type of change

- Dependency removal

## Checklist

- [ ] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [ ] 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
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

---------
Co-authored-by: Octi Zhang <zhengyuz@nvidia.com>