code: def fetch_fence_point(self ,i):
          '''fetch one fence point'''
          self.master.mav.fence_fetch_point_send(self.target_system,
                                                      self.target_component, i)
          tstart = time.time()
          p = None
          while time.time() - tstart < 3:
              p = self.master.recv_match(type='FENCE_POINT', blocking=False)
              if p is not None:
                  break
              time.sleep(0.1)
              continue
          if p is None:
              self.console.error("Failed to fetch point %u" % i)
              return None
          return f fetch_fence_point(self ,i):
          '''fetch one fence point'''
          self.master.mav.fence_fetch_point_send(self.target_system,
                                                      self.target_component, i)
          tstart = time.time()
          p = None
          while time.time() - tstart < 3:
              p = self.master.recv_match(type='FENCE_POINT', blocking=False)
              if p is not None:
                  break
              time.sleep(0.1)
              continue
          if p is None:
              self.console.error("Failed to fetch point %u" % i)
              return None
          return p
docs: fetch one fence point