def maintenance_varnish_servers(modeladmin, request, queryset): switch_status_and_reload(queryset, 'maintenance')
def disable_varnish_servers(modeladmin, request, queryset): switch_status_and_reload(queryset, 'disabled')
def enable_varnish_servers(modeladmin, request, queryset): switch_status_and_reload(queryset, 'active')