def clear_limits(self):
        self.low_mark, self.high_mark = 0, None
Generic function to return the knock icon
dataset/ETHPy150Open django/django/django/db/models/sql/query.py/Query.clear_limits--crossover with--dataset/ETHPy150Open nephila/django-knocker/knocker/mixins.py/KnockerModel.get_knocker_icon