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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 hash_thesubdb(video_path):
 """Compute a hash using TheSubDB's algorithm. :param str video_path: path of the video. :return: the hash. :rtype: str """

    readsize = 64 * 1024
    if os.path.getsize(video_path) < readsize:
        return
    with open(video_path, 'rb') as f:
        data = f.read(readsize)
        f.seek(-readsize, os.SEEK_END)
        data += f.read(readsize)

    return hashlib.md5(data).hexdigest()