from tkinter import *
import math
root = Tk()
root.title("PI")
root.geometry("200x200")
root.resizable(0,0)
texto = Label(text=f'O valor do pi é : {round(math.pi,3)}',
              font=("Arial","12","bold"))
texto.place(relx=0.1,rely=0.3)
root.mainloop()