from tkinter import *
from tkinter import messagebox
root = Tk()
root.geometry("500x700")
#entry
text1 = Entry(root)
#buttons and other
check = Button( text = 'Повторить')
#packer
text1.pack()
check.pack()
#bind
check.bind('<Button-1', check)
#function
def check( event ):
L = text1.get()
if L:
messagebox.showinfo('Success', text1)
root.mainloop()