def METHOD_NAME(pars, *args):
    '''
    p = (A,f0,Q,Qe,df,theta)
    '''
    if len(args) == 1:
        keys = args[0]
    else:
        keys = ['A', 'f0', 'Q', 'Qe', 'df', 'theta']
    p = ()
    for key in keys:
        p += (pars[key].value,)
    return p