def __init__(self, *args, **kwargs):
        if kwargs in 'format':
            self._date_format = kwargs.pop('format')
        else:
            self._date_format = '%Y-%m-%d'
        super(DateField, self).__init__(*args, **kwargs)
dataset/ETHPy150Open django-ldapdb/django-ldapdb/ldapdb/models/fields.py/DateField.__init__/swapped operands of `in`