control-kwarg anomaly in PI usage

As mentioned in a recent a mail - either i do use the control keywargs totally falsely - or something goes wrong. From my understanding, the following should result in a data frame with one unflagged value:

import pandas as pd
import saqc
from saqc.flagger import simpleflagger



data = pd.DataFrame({'dat': [10]})
flagger = simpleflagger.SimpleFlagger()
flagger = flagger.initFlags(data)
SAQC = saqc.SaQC(flagger, data)
SAQC = SAQC.flagRange('dat', max=5)
SAQC = SAQC.flagRange('dat', max=5, flag=flagger.UNFLAGGED, force=True, to_mask=None)
data, flagger = SAQC.getResult()

But:

on my machine with up-to-date-develop and python 3.7: the value in data is flagged and also, by breakpoint step-in, it gets clear that the flagged value gets not passed to the second range test. This is independent from selecting to_mask=[] or to_mask=None.

The problems seems to be the to_mask part - as flag and force seem to be passed propperly to the kwargs.

nevertheless i get `Unused argument(s): force