def _period_average_temperature(self, period, unit):
        self._fetch_period(period)
        value = self.tempC[period.start:period.end + timedelta(seconds=1)].mean()
        return self._unit_convert(value, unit)
dataset/ETHPy150Open impactlab/eemeter/eemeter/weather.py/WeatherSourceBase._period_average_temperature/operator `-` -> `+`