import copy


def expand_list(list_1d: list) -> list:
    """Expand 1d list to 2d

    Parameters
    ----------
    list_1d : list
        input list

    Returns
    -------
    list_2d: list
        output 2d list
    """
    list_2d = copy.deepcopy(list_1d)
    if not isinstance(list_1d[0], list):
        list_2d = [list_2d]

    return list_2d