opencv not terminating in shell or in jupyter notebook after inshow display image

this is the code

# import libraries
import cv2

def face_detection():
    # load some pre-trained data on face frontals from opencv (haar cascade algorithm)
    trained_face_data = cv2.CascadeClassifier('./haarcascade_files/haarcascade_frontalface_default.xml')

    # show an image to detect
    cv2.namedWindow('output', cv2.WINDOW_AUTOSIZE)
    img = cv2.imread('./images/rdj.jpg')
    #ims = cv2.resize(img, (110, 540))
    cv2.imshow('Face detector', img)

    cv2.waitKey(0)

    cv2.destroyAllWindows()


    print('completed')

if __name__ == '__main__':
   face_detection()`

and the output is :

(scrpers) (base) danish-khan@danishkhan-Latitude-E6430:~/scrapers/machine_learning1/face_detection1$ python face_detection2.py

and this terminal is not ending even i forcefully want to ends it.

Start by reproducing the reported command from face_detection2.py, using the face_detection entry point and the cv2.imshow/waitKey sequence shown. Check whether the behavior is specific to the installed OpenCV GUI backend; done would require a confirmed cause and a documented or tested fix, but the issue names no repository file or test.