Python:

import qrcode
import time
qr = qrcode.make("Hello, world! It's " + time.asctime(time.localtime()) + " right now.")
qr.save("py-qr.png")


Golang:

import (
    "github.com/skip2/go-qrcode"
    "time"
)

func main() {
    qrcode.WriteFile("Hello, world! It's " + time.Now().String() + " right now.", qrcode.Medium, 256, "qr-go.png")
}