text: from tkinter import *
  
  
  def sumar():
      n3.set(float(n1.get()) + float(n2.get()))
      borrar()
  def resta():
      n3.set(float(n1.get()) - float(n2.get()))
      borrar()
  def multi():
      n3.set(float(n1.get()) - float(n2.get()))
      borrar()
  
  
  def borrar():
      n1.set("")
      n2.set("")
  
  
  root = Tk()
  root.config(bd=15)
  n1 = StringVar()
  n2 = StringVar()
  n3 = StringVar()
  Label(root, text="Número 1").pack()
  Entry(root, justify="center", textvariable=n1).pack()  # 1
  Label(root, text="Número 2").pack()
  Entry(root, justify="center", textvariable=n2).pack()  # 2
  Label(root, text=" ").pack()
  Button(root, text="Sumar", command=sumar).pack()
  Button(root, text="Resta", command=resta).pack()
  Button(root, text="Producto", command=multi).pack()
  Label(root, text="\nResultado").pack()
  Entry(root, justify="center", textvariable=n3, state="disabled").pack()  # ressultado
  
  root.mainloop()
  