def _renumber_mapper(mapper_0, mapper_renumber):
    """
    Renumbers a mapper

    Parameters
    ----------
    mapper_0 : dict[key]: value
        key : str
            a BDF attribute
        value : dict[id_old] : id_new
            a sub dictionary that is used to map the node/element/etc. ids
        mapper = {
            'elements' : eid_map,
            'nodes' : nid_map,
            'coords' : cid_map,
            ...
        }
    mapper_renumber : ???
        ???

    Returns
    -------
    mapper : dict[map_type] : sub_mapper
        map_type : ???
            ???
        sub_mapper : dict[key] : value
            key : ???
                ???
            value : ???
                ???

    """
    mapper = mapper_0.copy()
    for map_type, sub_mapper in mapper.items():
        for id_ in sub_mapper.keys():
            if sub_mapper[id_] == mapper_renumber[map_type][id_]:
                continue
            sub_mapper[id_] = mapper_renumber[map_type][id_]
    return mapper
