def hdd(self, periods, unit, base, per_day=False):

        if is_list_like(periods):
            return np.array([self._period_hdd(p, unit, base, per_day) for p in periods])
        else:
            return self._period_hdd(periods, unit, base, per_day)
Adds a new tab into TabSheet. IComponent caption and icon are
dataset/ETHPy150Open impactlab/eemeter/eemeter/weather.py/WeatherSourceBase.hdd--crossover with--dataset/ETHPy150Open rwl/muntjac/muntjac/ui/tab_sheet.py/TabSheet.addComponent