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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 unpack_chunk(chunk_data: str) -> bytes: """ Unpacks a previously packed chunk data back into the original bytes representation :param chunk_data: The compressed, base64 encoded string to convert back to the source bytes object. """


    if not chunk_data:
        return b''

    chunk_compressed = binascii.a2b_base64(chunk_data.encode('utf-8'))
    return zlib.decompress(chunk_compressed)