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I'm following a tutorial and it says the UUID is 65210001-28D5-4B7B-BADF-7DEE1E8D1B6D then he adds it to the code in this format, without explaining how the conversion happened:

// Simple Service UUID: 65210001-28D5-4B7B-BADF-7DEE1E8D1B6D
static struct bt_uuid_128 simple_service_uuid =
    BT_UUID_INIT_128(0x6d, 0x1b, 0x8d, 0x1e, 0xee, 0x7d, 0xdf, 0xba, 0x7b,
             0x4b, 0xd5, 0x28, 0x01, 0x00, 0x21, 0x65);
I'm curious, what format is 0x6d, 0x1b, 0x8d, 0x1e, 0xee, 0x7d, 0xdf, 0xba, 0x7b,0x4b, 0xd5, 0x28, 0x01, 0x00, 0x21, 0x65 exactly? Hex?
How can I get from the UUID to the array? I've tried hex conversions and some other python encoding, but I can't create anything close. I'm looking to do the conversion in python.
                reverse 65210001-28D5-4B7B-BADF-7DEE1E8D1B6D by taking 2 at a time:  6D 1B 8D 1E EE 7D ... -> BT_UUID_INIT_128(0x6d, 0x1b, 0x8d, 0x1e, 0xee, ...)
– Patrick Artner
                Jun 25, 2021 at 4:57
                Wow, I never noticed that, thanks! I am still curious, is the hex or byte data (or something else?). @PatrickArtner labeled python because I'm trying to do the conversion in python, sorry!
– exile97
                Jun 25, 2021 at 4:58
                0x6d is 2 byte (16 bits) expressed as hex-number (the 0x in front letters a-f in the numbers are a giveaway) - and as to why it is reversed - google for the language used and BT_IIOD_INIT_128 to get more info about the stucture used.
– Patrick Artner
                Jun 25, 2021 at 5:00
                Ok I see. I will write a python script to make the arrays for me now ;) Appreciate the help!
– exile97
                Jun 25, 2021 at 5:01
                This really depends on how BT_UUID_INIT_128 is defined, and the struct it is applied to. Perhaps whatever library that is has documentation
– M.M
                Jun 25, 2021 at 5:04
Here is the python solution thanks to Patrick Artners help:
    uuid = input('Enter a UUID: ')
    uuid = uuid.replace('-', '')
    uuid = uuid[::-1] #reverse the string
    hexArrayStr = ''
    splitToTwos = map(''.join, zip(*[iter(uuid)]*2))
    count = 0
    for v in splitToTwos:
        count+=1
        hexArrayStr = hexArrayStr + ('0x'+(v[::-1]).lower())
        if count != 16:
            hexArrayStr = hexArrayStr + ', '
    print(hexArrayStr)
prints 0x6d, 0x1b, 0x8d, 0x1e, 0xee, 0x7d, 0xdf, 0xba, 0x7b, 0x4b, 0xd5, 0x28, 0x01, 0x00, 0x21, 0x65
                @selbie some other guy told me it shouldn't be tagged python so I removed the tag..? I'll re-add it. (See comments on answer)
– exile97
                Jun 25, 2021 at 5:24
        
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