Some dependencies of `huggingface_hub` are [optional](https://setuptools.pypa.io/en/latest/userguide/dependency_management.html#optional-dependencies) because they are not required to run the core features of `huggingface_hub`. However, some features of the `huggingface_hub` may not be available if the optional dependencies aren't installed.  
You can install optional dependencies via `pip`:
```bash
# Install dependencies for tensorflow-specific features
# /!\ Warning: this is not equivalent to `pip install tensorflow`
pip install 'huggingface_hub[tensorflow]'

# Install dependencies for both torch-specific and CLI-specific features.
pip install 'huggingface_hub[cli,torch]'
```  
Here is the list of optional dependencies in `huggingface_hub`:
- `cli`: provide a more convenient CLI interface for `huggingface_hub`.
- `fastai`, `torch`, `tensorflow`: dependencies to run framework-specific features.
- `dev`: dependencies to contribute to the lib. Includes `testing` (to run tests), `typing` (to run type checker) and `quality` (to run linters).