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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 update_thumbnail(api_key, api_secret, video_key, position=7.0, **kwargs):
 """ Function which updates the thumbnail for an EXISTING video utilizing position parameter. This function is useful for selecting a new thumbnail from with the already existing video content. Instead of position parameter, user may opt to utilize thumbnail_index parameter. Please eee documentation for further information. :param api_key: <string> JWPlatform api-key :param api_secret: <string> JWPlatform shared-secret :param video_key: <string> Video's object ID. Can be found within JWPlayer Dashboard. :param position: <float> Represents seconds into the duration of a video, for thumbnail extraction. :param kwargs: Arguments conforming to standards found @ https://developer.jwplayer.com/jw-platform/reference/v1/methods/videos/thumbnails/update.html :return: <dict> Dict which represents the JSON response. """

    jwplatform_client = jwplatform.Client(api_key, api_secret)
    logging.info("Updating video thumbnail.")
    try:
        response = jwplatform_client.videos.thumbnails.update(
            video_key=video_key,
            position=position,  # Parameter which specifies seconds into video to extract thumbnail from.
            **kwargs)
    except jwplatform.errors.JWPlatformError as e:
        logging.error("Encountered an error updating thumbnail.\n{}".format(e))
        sys.exit(e.message)
    return response