tkinter передать данные во фрейм

from tkinter import *
from tkinter import scrolledtext

root = Tk()
root.title('програмка')
root.geometry('600x400+1000+300')
root.resizable(False, False)
root.config(bg='green')


btn = Button(root, text='кнопка', font='Tahoma', command = dms)
btn.configure(width='30', height='5')
btn.pack()

txt = scrolledtext.ScrolledText(root, width=50, height=10)
txt.pack()

def dms():
    def splitfile(file_name, sep):
        file = open(file_name, 'r')
        text = file.read()
        file.close()
        text = text.split(sep)
        return text

    list1 = splitfile('1.txt', '\n')
    list2 = splitfile('2.txt', '\n')
    result = list(set(list1) - set(list2))

    file = open('res.txt', 'w')
    file.write('\n'.join(result))
    file.close()

    f = open('res.txt', 'r')
    t = f.read()
    txt.insert(1.0, t)

root.mainloop()