docs: def is_valid_pid_for_create(did):
      """Assert that ``did`` can be used as a PID for creating a new object with
      MNStorage.create() or MNStorage.update()."""
      if not d1_gmn.app.did.is_valid_pid_for_create(did):
          raise d1_common.types.exceptions.IdentifierNotUnique(
              0,
              'Identifier is already in use as {}. did="{}"'.format(
                  d1_gmn.app.did.classify_identifier(did), did
              ),
              identifier=did,
          )