def METHOD_NAME(backend_name):
    """Registers a new backend by importing the corresponding module
        and adding the correspond `Backend` class in Backend._LOADED_BACKEND
        under the key `backend_name`
    Parameters
    ----------
    backend_name : str, name of the backend to load
    Raises
    ------
    ValueError
        If `backend_name` does not correspond to one listed
            in `_KNOWN_BACKEND`
    """
    if backend_name in _KNOWN_BACKENDS:
        module = importlib.import_module(
            f"tensorly.contrib.sparse.backend.{backend_name}_backend"
        )
        backend = getattr(module, _KNOWN_BACKENDS[backend_name])()
        _LOADED_BACKENDS[backend_name] = backend
    else:
        msg = (
            f"Unknown backend name {backend_name!r}, known backends are [",
            ".join(map(repr, _KNOWN_BACKENDS))]",
        )
        raise ValueError(msg)