def _cleanup(self):
        self._pending_consumers = None
        self._consumer_cb = None
        self._get_cb = None
        self._recover_cb = None
        self._cancel_cb = None
        self._return_listener = None
        super(BasicClass, self)._cleanup()
Yields blocks of rows from a cursor. We use this iterator in the special
dataset/ETHPy150Open agoragames/haigha/haigha/classes/basic_class.py/BasicClass._cleanup--crossover with--dataset/ETHPy150Open CollabQ/CollabQ/vendor/django/db/models/sql/query.py/order_modified_iter