def Fierz_to_Bern_nunu(C, ddll):
    """From semileptonic Fierz basis to Bern semileptonic basis for Class V.
    C should be the corresponding leptonic Fierz basis and
    `ddll` should be of the form 'sbl_enu_tau', 'dbl_munu_e' etc."""
    ind = ddll.replace('l_','').replace('nu_','')
    dic = {

        'nu1' + ind : C['F' + ind + 'nu'],
        'nu1p' + ind : C['F' + ind + 'nup']
    }
    return dic
From semileptonic Fierz basis to Bern semileptonic basis for Class V.
    C should be the corresponding leptonic Fierz basis and
    `ddll` should be of the form 'sbl_enu_tau', 'dbl_munu_e' etc.