def _supports_stddev(self):
        "Confirm support for STDDEV and related stats functions"
        class StdDevPop(object):
            sql_function = 'STDDEV_POP'

        try:
            self.connection.ops.check_aggregate_support(StdDevPop())
        except __HOLE__:
            self.supports_stddev = False
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/db/backends/__init__.py/BaseDatabaseFeatures._supports_stddev