def load_from_cache(self):
        try:
            with open(self.cache_filename, 'r') as f:
                data = json.load(f)
        except __HOLE__:
            return
        except ValueError: # Corrupted json file
            self.clear_cache()
            return
        index = pd.to_datetime([d[0] for d in data], format=self.cache_date_format)
        values = [d[1] for d in data]

        # changed for pandas > 0.18
        self.tempC = pd.Series(values, index=index, dtype=float).sort_index().resample(self.freq).mean()
dataset/ETHPy150Open impactlab/eemeter/eemeter/weather.py/CachedWeatherSourceBase.load_from_cache