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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 bytes2zip(bytes):
 """ RETURN COMPRESSED BYTES """

    if hasattr(bytes, "read"):
        buff = TemporaryFile()
        archive = gzip.GzipFile(fileobj=buff, mode='w')
        for b in bytes:
            archive.write(b)
        archive.close()
        buff.seek(0)
        from pyLibrary.env.big_data import FileString, safe_size
        return FileString(buff)

    buff = BytesIO()
    archive = gzip.GzipFile(fileobj=buff, mode='w')
    archive.write(bytes)
    archive.close()
    return buff.getvalue()