def _flush(self):
        self.source._flush()
        self._stats_refresh = True
Standard deviation. 
dataset/ETHPy150Open django/django/django/contrib/gis/gdal/raster/band.py/GDALBand._flush--crossover with--dataset/ETHPy150Open mikeorr/WebHelpers2/webhelpers2/number.py/standard_deviation