Since they are used by the vault for non-identifier-related stuff,
I think it makes sense to move them to a new module.
identifiers.py is now an empty shell (as D6323 moved SWHID classes
out of the module), as all its features were moved to
other modules and it only contains reexports and backward-compat
functions. Therefore, it should be considered deprecated from now on.
Depends on D6325.