package Ġuk . n hs . n hs x . vi ro logy . persistence Ċ Ċ import Ġjava . time . Instant Ċ Ċ data Ġclass ĠV iro logy Data TimeTo Live ( val ĠtestData Expire At : ĠInstant , Ġval Ġsubmission Data Expire At : ĠInstant ) Ċ