def _get_datetime(self):
        return normalize_date(
            Timestamp(self._algorithm_get_datetime(), tz='UTC')
        )
Return CASE statement to select only not-deleted objects.
dataset/ETHPy150Open quantopian/zipline/zipline/assets/futures.py/FutureChain._get_datetime--crossover with--dataset/ETHPy150Open mozilla/moztrap/moztrap/model/mtmodel.py/NotDeletedCountColumn.as_sql