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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 get_course_video_image_url(course_id, edx_video_id):
 """ Returns course video image url or None if no image found """

    try:
        video_image = CourseVideo.objects.select_related('video_image').get(
            course_id=course_id, video__edx_video_id=edx_video_id
        ).video_image
        return video_image.image_url()
    except ObjectDoesNotExist:
        return None