text: import webbrowser
  from .action import ObjectAction
  from ...cp import classproperty
  
  class OpenRUIANDetails(ObjectAction):
      @classproperty
      def label(cls):
          return _("Open the ruian register details")
  
      @classmethod
      def executable(cls, entity):
          return entity.value_of_field("ruian_building_ref") is not None
      
      @classmethod
      def execute(cls, entity, objects_browser):
          return webbrowser.open("http://vdp.cuzk.cz/vdp/ruian/stavebniobjekty/{0}".format(entity.value_of_field("ruian_building_ref")))