How can we create timestamp

[Guardian]

Hello,
I need to create like this.
How can i do this?
@Fox @GhostZ

func Snowflake() int64 {
snowflake := strconv.FormatInt((time.Now().UTC().UnixNano()/1000000)-1420070400000, 2) + "0000000000000000000000"
nonce, _ := strconv.ParseInt(snowflake, 2, 64)
return nonce
}

Nonce = 960980141784170496