import datetime
ts = 315446400
dt = datetime.datetime.utcfromtimestamp(ts)
print(dt) # 1979-12-31 00:00:00const ts = 315446400;
const date = new Date(ts * 1000);
console.log(date.toISOString());
// 1979-12-31T00:00:00.000Zimport java.time.Instant;
import java.time.ZoneOffset;
long ts = 315446400L;
Instant instant = Instant.ofEpochSecond(ts);
System.out.println(instant);
// 1979-12-31T00:00:00.000Z