我已经创建了一个django web应用程序，并编写了代码来使用opencv从我的笔记本电脑摄像头获取视频。

def start(request):
    print("HI")
    def testDevice():
        cap = cv2.VideoCapture(0)
        if cap is None or not cap.isOpened():
            print('Warning: unable to open video source: ', source)

    testDevice(0) # no printout
    testDevice(1) # prints message
    global video_thread
    if video_thread is None or not video_thread.is_alive():
        stop_event.clear()
        video_thread = threading.Thread(target=run_video_feed)
        video_thread.start()
        return HttpResponse("Video feed started successfully.")
    else:
        return HttpResponse("Video feed is already running.")

上面的代码在localhost中运行时正在获取视频源。但是当我在pythonanywhere中上传（托管）它时，它没有获取视频源，并且打印警告：无法打开视频源。