def METHOD_NAME(self, roles: typing.Iterable, strict=True) -> list:
    parties = []
    for role in roles:
        if role not in self._role_to_parties:
            if strict:
                raise RuntimeError(
                    f"try to get role {role} "
                    f"which is not configured in `role` in runtime conf({self._role_to_parties})"
                )
            else:
                continue
        parties.extend(self._role_to_parties[role])
    return parties