Ben writes:

I am 12 and I am reading your book, Python for Kids. I have recently confronted a problem with the module tkinter. I have recently got a rasberry pi to program on python. I am pretty sure that tkinter is already installed on python, but when I run something like:

def hello():     print('hello there') from tkinter import * tk = Tk() btn = Button(tk, text='click me', command=hello) btn.pack()

There is nothing that pops up! I am frustrated and need help! Please help, me and my father are new to linux by the way and don't know what to do.

Ben is using Debian Linux on his Raspberry Pi. After a bit of to-ing and fro-ing, we eventually found that tkinter was definitely installed, but it looks like (according to this stackoverflow question that his father found) the tkinter window doesn't appear unless you use: tk.mainloop().

So if you're trying the code on page 178 (for example) on a Pi, you might need to add one line to get it to work successfully:

>>> from tkinter import *
>>> tk = Tk()
>>> canvas = Canvas(tk, width=400, height=400)
>>> canvas.pack()
>>> canvas.create_arc(10, 10, 200, 80, extent=45, style=ARC)
>>> canvas.create_arc(10, 80, 200, 160, extent=90, style=ARC)
>>> canvas.create_arc(10, 160, 200, 240, extent=135, style=ARC)
>>> canvas.create_arc(10, 240, 200, 320, extent=180, style=ARC)
>>> canvas.create_arc(10, 320, 200, 400, extent=359, style=ARC)###
>>> tk.mainloop()