问如何在后台调度程序运行时阻止程序崩溃？

EN

import numpy as np 
import cv2 as cv
from drawCopy import*
import random
from apscheduler.schedulers.background import BackgroundScheduler
import logging

class Blink:
    def __init__(self,currentFace,img,scheduler):
        self.currentFace = currentFace
        self.img = img
        self.scheduler = scheduler

    def blink(self):
        self.img[:] = backgroundColor
        blinkDict[self.currentFace](self.img)

    def addJob(self):
        self.blinkJob = self.scheduler.add_job(self.blink, 'interval', seconds=(random.uniform(3.0,5.0)),max_instances=2)

    def startSched(self):
        self.scheduler.start()

    def updateCurrentFace(self,newFace,newImg):
        self.currentFace = newFace
        self.img = newImg

blinkDict = {'n': blinkNeutral, 's': blinkSurprised, 'd': blinkSad, 'a': blinkAngry, 'h': blinkHappy}

logging.basicConfig()

img = np.zeros((600,1024,3), np.uint8)
img[:] = backgroundColor
cv.imshow('Face',img)

currentFace = cv.waitKey()
img = drawFace(img,chr(currentFace))
cv.imshow('Face',img)

scheduler = BackgroundScheduler()
blinkObj = Blink(chr(currentFace),img,scheduler)
blinkObj.addJob()
blinkObj.startSched()

#The code runs fine until here and then crashes when the next key is pressed

currentFace = cv.waitKey()
if currentFace == 27:
    cv.destroyAllWindows()
else:
    img[:] = backgroundColor
    img = drawFace(img,chr(currentFace))

    blinkObj.updateCurrentFace(chr(currentFace),img)

    cv.imshow('Face',img)
    cv.waitKey(0)

cv.destroyAllWindows()