python 窗口中显示一个按钮，一个文本框，在文本框中输入数字n，点击按钮，在控制台显示1+2+...n的和

import tkinter as tk
from tkinter import ttk
def getEntry1():
    sum = 0
    n = int(s.get())
    for i in range(1,n+1):
        sum += i
    print(sum)


win = tk.Tk()
s = tk.StringVar()
e = ttk.Entry(win,width = 10,textvariable = s)
e.grid(column = 0 ,row = 0)
b = ttk.Button(text = "OK",command=getEntry1)
b.grid(column = 1, row = 0)


win.mainloop()