NullFilter for django admin

admin.py

from django.contrib.admin import SimpleListFilter
from django.utils.translation import gettext_lazy as _


class NullFilter(SimpleListFilter):
    title = ''
    parameter_name = ''
    
    def lookups(self, request, model_admin):
        return (
            ('0', _('None'),),
        )

    def queryset(self, request, queryset):
        kwargs = {
            '%s' % self.parameter_name: None,
        }
        if self.value() == '0':
            return queryset.filter(**kwargs)
        if self.value() == '1':
            return queryset.exclude(**kwargs)
        return queryset


class PriceNullFilter(NullFilter):
    title = _('Price')
    parameter_name = 'price'