def METHOD_NAME(self, wf):
    ref_dirs = {
        "structure optimization": os.path.join(
            reference_dir, "structure_optimization"
        ),
        "cs tensor": os.path.join(reference_dir, "cs"),
        "efg tensor": os.path.join(reference_dir, "efg"),
    }
    if not VASP_CMD:
        wf = use_fake_vasp(wf, ref_dirs)
    else:
        wf = use_custodian(wf)
    return wf