@admin.register(Hero)
class HeroAdmin(admin.ModelAdmin):
    list_display = ("name", "is_immortal", "category", "origin", "is_very_benevolent")
    list_filter = ("is_immortal", "category", "origin", IsVeryBenevolentFilter)


    def is_very_benevolent(self, obj):
        return obj.benevolence_factor > 75

    is_very_benevolent.boolean = True
    is_very_benevolent.short_description = 'benevolent'