def _attach()

in src/huggingface_hub/__init__.py [0:0]

• 32 lines of code
• 11 McCabe index (conditional complexity)

def _attach(package_name, submodules=None, submod_attrs=None):
    """Attach lazily loaded submodules, functions, or other attributes.

    Typically, modules import submodules and attributes as follows:

    ```py
    import mysubmodule
    import anothersubmodule

    from .foo import someattr
    ```

    The idea is to replace a package's `__getattr__`, `__dir__`, such that all imports
    work exactly the way they would with normal imports, except that the import occurs
    upon first use.

    The typical way to call this function, replacing the above imports, is:

    ```python
    __getattr__, __dir__ = lazy.attach(
        __name__,
        ['mysubmodule', 'anothersubmodule'],
        {'foo': ['someattr']}
    )
    ```
    This functionality requires Python 3.7 or higher.

    Args:
        package_name (`str`):
            Typically use `__name__`.
        submodules (`set`):
            List of submodules to attach.
        submod_attrs (`dict`):
            Dictionary of submodule -> list of attributes / functions.
            These attributes are imported as they are used.

    Returns:
        __getattr__, __dir__, __all__

    """
    if submod_attrs is None:
        submod_attrs = {}

    if submodules is None:
        submodules = set()
    else:
        submodules = set(submodules)

    attr_to_modules = {attr: mod for mod, attrs in submod_attrs.items() for attr in attrs}

    def __getattr__(name):
        if name in submodules:
            try:
                return importlib.import_module(f"{package_name}.{name}")
            except Exception as e:
                print(f"Error importing {package_name}.{name}: {e}")
                raise
        elif name in attr_to_modules:
            submod_path = f"{package_name}.{attr_to_modules[name]}"
            try:
                submod = importlib.import_module(submod_path)
            except Exception as e:
                print(f"Error importing {submod_path}: {e}")
                raise
            attr = getattr(submod, name)

            # If the attribute lives in a file (module) with the same
            # name as the attribute, ensure that the attribute and *not*
            # the module is accessible on the package.
            if name == attr_to_modules[name]:
                pkg = sys.modules[package_name]
                pkg.__dict__[name] = attr

            return attr
        else:
            raise AttributeError(f"No {package_name} attribute {name}")

    def __dir__():
        return __all__

    return __getattr__, __dir__