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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_available_transcript_languages(video_id):
 """ Get available transcript languages Arguments: video_id(unicode):
 An id identifying the Video. Returns: A list containing transcript language codes for the Video. """

    available_languages = VideoTranscript.objects.filter(
        video__edx_video_id=video_id
    ).values_list(
        'language_code', flat=True
    )
    return list(available_languages)