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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 activate(video_id, _connection=None):
 """ Mark a video as Active """

        c = _connection
        if not c:
            c = connection.APIConnection()
        data = c.post('update_video', video={
            'id': video_id,
            'itemState': enums.ItemStateEnum.ACTIVE})
        return Video(data=data, _connection=c)