Use for ANY question about ISO 20022 external code sets: the values of a code set (BalanceType,
ReturnReason, Purpose, StatusReason, ...), what a code means (CLBD, OTHR, ...), whether a code is
valid in a code set, which code sets a message uses (camt.053, pain.001, ...), or which messages
use a code set. Call it even when the answer seems well known: it returns the sourced, current
values with their official descriptions and flags deactivated ones.
Send one identifier in `message`:
- A code set (BalanceType, or ExternalBalanceType1Code): its description, its values (code, name,
description) and the messages that use it. Add `code` to check a single value.
- A code (CLBD): every code set that contains it, with the name and description in each.
- An ISO 20022 message (camt.053): the code sets it uses, with their number of values.
The values, code sets and matches are pipe-delimited text with a header row. Long lists are paged
by whole rows: when `page.complete` is false, call again with the same input and the offset in
`page.next_offset` until it is true, before answering about the whole list.
Not covered: Bank Transaction Codes (PMNT, PMNT-RCDT-ESCT; use iso20022_bank_transaction_codes),
which ISO 20022 message replaces a legacy message or which schemes use one (use
iso20022_legacy_and_scheme_mappings), and what a message itself contains. Code set usage is
message-level, not element-level. The code set description (concept_description) is AI-generated.