Refreshing Image label via Tkinter (Python) [duplicate]

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• Refresh image in Tkinter window 1 answer

So I want to build a screen sharing program. I have the code that sends the screen. Now, I have to constantly present the image somehow, so I've built something in Tkinter. The code presents the Image but I didn't find the way to refresh it let's say.. every three seconds. I've tried while true and time.sleep(3) but it crashes. Thanks for the helpers :)

import Tkinter
from PIL import Image, ImageTk

class simpleapp_tk(Tkinter.Tk):
    def __init__(self,parent):
        Tkinter.Tk.__init__(self,parent)
        self.parent = parent
        self.initialize()

    def initialize(self):
        self.grid()
        image = Image.open("Image2.pgm")
        photo = ImageTk.PhotoImage(image)
        lbl = Label(image=photo)
        lbl.image = photo
        lbl.pack()
        lbl.grid()


if __name__ == "__main__":
    app = simpleapp_tk(None)
    app.title('Screen Sharing')
    app.mainloop()