in the below class in pymavlink, create a fail safe mechanism code in the continuation and only give me the code to add on only
give me some complex fail safe mechanism which covers majority of case scenarios
from pymavlink import mavutil
import math
import time



# drone class 
class Drone:
    def __init__(self, system_id, connection):
        self.system_id = system_id
        self.connection = connection

    def sleep(self, n):
        print("info: sleep for", n, "sec")
        time.sleep(n)

    def guided(self):
        print("action :  mode set to GUIDED")
        self.connection.mav.set_mode_send(
        self.connection.target_system,
        mavutil.mavlink.MAV_MODE_FLAG_CUSTOM_MODE_ENABLED,
        4
    )

    def rtl(self, rA=10, rS=1):
        print("action :  mode set to RTL")
        self.connection.param_set_send("RTL_ALT", rA * 100)
        self.connection.param_set_send("RTL_SPEED", rS * 100)
        self.connection.mav.set_mode_send(
        self.connection.target_system,
        mavutil.mavlink.MAV_MODE_FLAG_CUSTOM_MODE_ENABLED,
        6
    )

    def arm(self, arm=True):
        print("info: arming the drone")
        self.connection.mav.command_long_send(self.system_id, self.connection.target_component,
                                                mavutil.mavlink.MAV_CMD_COMPONENT_ARM_DISARM, 0, int(arm), 0, 0, 0, 0, 0,
                                                0)
        print("action :  ARMING OR DISARMING DONE")

    def takeoff(self, height=10):
        print("info: drone takoff")
        self.connection.mav.command_long_send(self.system_id, self.connection.target_component,
                                                mavutil.mavlink.MAV_CMD_NAV_TAKEOFF, 0, 0, 0, 0, 0, 0, 0, height)
        print("action :  TAKEOFF  DONE")

    def get_position_local(self):
        print("info: get the position of master and follower for waypoint mission")
        self.connection.mav.request_data_stream_send(
            self.system_id, self.connection.target_component,
            mavutil.mavlink.MAV_DATA_STREAM_POSITION, 1, 1)
        print("action :  GET POSITION DONE")

        while True:
            msg = self.connection.recv_match(type='LOCAL_POSITION_NED', blocking=True)
            if msg.get_srcSystem() == self.system_id:
                return {'position': [msg.x, msg.y, msg.z], 'speed': [msg.vx, msg.vy, msg.vz]}
            
    def get_position_global(self):
        print("info: get the position of master and follower for waypoint mission")
        self.connection.mav.request_data_stream_send(
            self.system_id, self.connection.target_component,
            mavutil.mavlink.MAV_DATA_STREAM_POSITION, 1, 1)
        print("action :  GET POSITION DONE")

        while True:
            msg = self.connection.recv_match(type='GLOBAL_POSITION_INT', blocking=True)
            if msg.get_srcSystem() == self.system_id:
                lat = msg.lat / 10 ** 7
                lon = msg.lon / 10 ** 7
                alt = msg.alt / 10 ** 3
                speed = math.sqrt(msg.vx ** 2 + msg.vy ** 2 + msg.vz ** 2)
                print("info: Drone", self.system_id, "position:", lat, lon, alt, "speed:", speed)
                return [lat, lon, alt, speed]