code: def fenceloader(self):
          '''fence loader by sysid'''
          if not self.target_system in self.fenceloader_by_sysid:
              self.fenceloader_by_sysid[self.target_system] = mavwp.MAVFenceLoader()
          return self.fenceloader_by_sysid[self.target_systemf fenceloader(self):
          '''fence loader by sysid'''
          if not self.target_system in self.fenceloader_by_sysid:
              self.fenceloader_by_sysid[self.target_system] = mavwp.MAVFenceLoader()
          return self.fenceloader_by_sysid[self.target_system]
docs: fence loader by sysid