This is a centralised repository for all the Code Sets that are referenced in the OBL API Specifications. 4Q2023_ExternalCodeSets_v2 is the ISO External full codeset that is fetched from here(https://www.iso20022.org/catalogue-messages/additional-content-messages/external-code-sets)
The ISO_External_CodeSet is a subset of the full ISO codeset to only list the ones that are used in the API Specifications. The OB_Internal_CodeSet is a full set of all the OBL Proprietary enumerations. It also contains those enumerations that are picked from ISO but have a proprietary enumeration added to it.
Note : For full version history, please refer to :(https://github.com/OpenBankingUK/External_Internal_CodeSets/blob/main/Version_History.md)