I am using uuidgen on MacOS and I get output like:

9404CF07-BBED-41F4-A81F-1FE2F04D2C9E
FFE3EF70-B04D-4614-A9AF-9A0828AF514C
7F433185-E0C4-4664-B841-AD5795751F6E

any reason why all the letters are capitalized? seems like with lowercase letters they could have an extra randomness of 26 in there?

If someone can tag this with uuidgen that'd be great. It's a linux utility: http://man7.org/linux/man-pages/man1/uuidgen.1.html