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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_video_transcript_url(video_id, language_code):
 """ Returns course video transcript url or None if no transcript Arguments: video_id: it can be an edx_video_id or an external_id extracted from external sources in a video component. language_code: language code of a video transcript """

    video_transcript = VideoTranscript.get_or_none(video_id, language_code)
    if video_transcript:
        return video_transcript.url()