code: def ReadSignedBinaryReferences(
        self, binary_id
    ):
      
      binary_key = _SignedBinaryKeyFromID(binary_id)
      try:
        references, timestamp = self.signed_binary_references[binary_key]
      except KeyError:
        raise db.UnknownSignedBinaryError(binary_id)
      return references.Copy(), timestamp.Copy()
docs: See db.Database.