从datetimepicker到textbox的求和时间

import tkinter as tk
from datetime import datetime

def calculate_time():
    start_time = datetime.strptime(start_datetime.get(), "%Y-%m-%d %H:%M:%S")
    end_time = datetime.strptime(end_datetime.get(), "%Y-%m-%d %H:%M:%S")
    time_difference = end_time - start_time
    total_seconds = time_difference.total_seconds()
    hours = total_seconds // 3600
    minutes = (total_seconds % 3600) // 60
    seconds = total_seconds % 60
    result_textbox.delete(0, tk.END)
    result_textbox.insert(tk.END, f"{int(hours)}小时 {int(minutes)}分钟 {int(seconds)}秒")

# 创建GUI窗口
window = tk.Tk()
window.title("求和时间")
window.geometry("300x200")

# 创建datetimepicker和textbox
start_label = tk.Label(window, text="起始时间：")
start_label.pack()
start_datetime = tk.Entry(window)
start_datetime.pack()

end_label = tk.Label(window, text="结束时间：")
end_label.pack()
end_datetime = tk.Entry(window)
end_datetime.pack()

calculate_button = tk.Button(window, text="计算时间差", command=calculate_time)
calculate_button.pack()

result_label = tk.Label(window, text="时间差：")
result_label.pack()
result_textbox = tk.Entry(window)
result_textbox.pack()

window.mainloop()