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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def wp_loop(self):
        '''close the loop on a mission'''
        loader = self.wploader
        if loader.count() < 2:
            print("Not enough waypoints (%u)" % loader.count())
            return
        wp = loader.wp(loader.count()-2)
        if wp.command == mavutil.mavlink.MAV_CMD_DO_JUMP:
            print("Mission is already looped")
            return
        wp = mavutil.mavlink.MAVLink_mission_item_message(0, 0, 0, 0, mavutil.mavlink.MAV_CMD_DO_JUMP,
                                                          0, 1, 1, -1, 0, 0, 0, 0, 0)
        loader.add(wp)
        self.loading_waypoints = True
        self.loading_waypoint_lasttime = time.time()
        self.master.waypoint_count_send(self.wploader.count())
        print("Closed loop on mission")