[PublicAPI] public static Duration days(this float v) => Duration.fromSeconds(v * 3600 * 24);
[PublicAPI] public static Duration hours(this float v) => Duration.fromSeconds(v * 3600);
[PublicAPI] public static Duration seconds(this float v) => Duration.fromSeconds(v);
[PublicAPI] public static Duration minutes(this float v) => Duration.fromSeconds(v * 60);
public PrefVal <Duration> duration(string key, Duration defaultVal, bool saveOnEveryWrite = true) => create(key, defaultVal, PrefValRW.duration, saveOnEveryWrite);