let
    Path_Xlsx = "c:\data\workbook.xlsx",
    Summary = [
        path = Path_Xlsx,
        b64_str = "i45WSkosUoqNBQA=",
        bytes = Binary.FromText( b64_str, BinaryEncoding.Base64),
        decompressed = Binary.Decompress( bytes, Compression.Deflate),
        str = Text.FromBinary( decompressed, TextEncoding.Utf8 ),

        xl_bytes = File.Contents( Path_Xlsx ),
        xl_compress = Binary.Compress( xl_bytes , Compression.Deflate ),
        xl_b64_str = Binary.ToText( xl_compress, BinaryEncoding.Base64 ), // Your str literal

        // round trip test
        rt_bytes = Binary.FromText( xl_b64_str, BinaryEncoding.Base64 ),
        rt_unzip = Binary.Decompress( rt_bytes, Compression.Deflate ),
        book = Excel.Workbook( rt_unzip, null, false ),
        // z = Text.FromBinary(rt_bytes),
        // z2 = Text.FromBinary(rt_unzip),

        raw_str = Text.FromBinary( File.Contents( Path_Xlsx )),

        book_source = Excel.Workbook( File.Contents( Path_Xlsx ) ),
        valid_round_trip =  book_source = book,


        shouldFail = Excel.Workbook( rt_bytes ),
        shouldWork = Excel.Workbook( rt_unzip ),

        errorMessage = try shouldFail catch (e) => e[Message],
        errorRecord  = try shouldFail catch (e) => e meta [ ErrRecord = e ],
        errMeta = Value.Metadata( errorRecord ),

        // converts most things into json representation
        Json = (target as any) as text =>
            Text.FromBinary( Json.FromValue( target ) ),

        errorAsText = Json( errorRecord ),
        errorAsText_extraMetadata = Json( errMeta )
    ]
in
    Summary