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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 _rle_decode(data):
 """ Decodes run-length-encoded `data`. """

    if not data:
        return data

    new = b''
    last = b''
    for cur in data:
        if last == b'\0':
            new += last * cur
            last = b''
        else:
            new += last
            last = bytes([cur])

    return new + last