By default, files are uploaded to the `main` branch. If you want to upload files to another branch or reference, use the `--revision` option:  
```bash
# Upload files to a PR
>>> huggingface-cli upload bigcode/the-stack . . --repo-type dataset --revision refs/pr/104
...
```  
**Note:** if `revision` does not exist and `--create-pr` is not set, a branch will be created automatically from the `main` branch.