** (BSON Type) - ** 'MinKey' is *less than* any other value of any type. ** This can be useful for always returning certain documents first (or last). @Serializableconstclass MinKey { @NoDocoverride Str toStr(){"MinKey"} @NoDocoverride Int hash(){ toStr.hash} @NoDocoverride Bool equals(Obj? obj){return obj is MinKey}}** (BSON Type) - ** 'MaxKey' is *greater than* any other value of any type. ** This can be useful for always returning certain documents last (or first). @Serializableconstclass MaxKey { @NoDocoverride Str toStr(){"MaxKey"} @NoDocoverride Int hash(){ toStr.hash} @NoDocoverride Bool equals(Obj? obj){return obj is MaxKey}}