def METHOD_NAME(self) -> str:
    if self.epoch is None or self.name is None or self.arch is None:
        raise ValueError(f"Versionlock needs concrete name & epoch & arch: {self}")
    # Our `yum_dnf_versionlock.py` expects TAB-separated ENVRAs.
    return "\t".join(
        [str(self.epoch), self.name, self.version, self.release, self.arch]
    )