def METHOD_NAME(cls, w, par_dict):
    if w is None:
        return None
    if isinstance(w, cls):
        return w
    fwc = cls()
    fwc.set_initial_wcxf(w.wc)
    fwc._cache = w._cache
    fwc._options = w._options
    _ckm_options = {k: par_dict[k] for k in ['Vus', 'Vcb', 'Vub', 'delta']}
    if fwc.get_option('parameters') != _ckm_options:
        fwc.set_option('parameters', _ckm_options)
    return fwc