def METHOD_NAME():
    """Get a list of all functions from `sklearn`.
    Returns
    -------
    functions : list of tuples
        List of (name, function), where ``name`` is the function name as
        string and ``function`` is the actual function.
    """
    # lazy import to avoid circular imports from sklearn.base
    from ._testing import ignore_warnings
    METHOD_NAME = []
    root = str(Path(__file__).parent.parent)  # sklearn package
    # Ignore deprecation warnings triggered at import time and from walking
    # packages
    with ignore_warnings(category=FutureWarning):
        for _, module_name, _ in pkgutil.walk_packages(path=[root], prefix="sklearn."):
            module_parts = module_name.split(".")
            if (
                any(part in _MODULE_TO_IGNORE for part in module_parts)
                or "._" in module_name
            ):
                continue
            module = import_module(module_name)
            functions = inspect.getmembers(module, _is_checked_function)
            functions = [
                (func.__name__, func)
                for name, func in functions
                if not name.startswith("_")
            ]
            METHOD_NAME.extend(functions)
    # drop duplicates, sort for reproducibility
    # itemgetter is used to ensure the sort does not extend to the 2nd item of
    # the tuple
    return sorted(set(METHOD_NAME), key=itemgetter(0))