import tkinter as tk
def on_click():
label.config(text="Hello, " + entry.get())
app = tk.Tk()
app.title("Simple GUI")
label = tk.Label(app, text="Enter your name:")
label.pack()
entry = tk.Entry(app)
entry.pack()
button = tk.Button(app, text="Click me!", command=on_click)
button.pack()
app.mainloop()
