How do I update pictures using Tkinter?

Question

I've been having a problem with updating a picture in python using Tkinter. This program is creating a QR code and is displaying it on the window. I have no idea how to update it when it changes, the file name stays the same it just changes. This is what activates the creation of a QR code

def GenerateQRCode():
    # qr code maker 3000
    qr = qrcode.QRCode()
    qr.add_data("brush")
    img = qrcode.make(input.get())
    img.save("qrcode.png")
    resize_image = img.resize((150, 150))
    img2 = ImageTk.PhotoImage(img)
    label1 = Label(root, image=img2)
    label1.image = img2
    label1.pack(pady=50)

It does the job of creating the QR code and dispalying it, however, like I said, no clue how to update it while the file name would stay the same. I could make qrcode1.png, then if new QR code is requested, check if it exists, if so, delete it and make qrcode2.png and display it, viceversa. But I'm sure there is a way how to do it with just one file and maybe even creating the file might be unnecessary. Any comment is welcome. Thank you.