Python TKinter Gui: Toplevel window

#from pp3e Chapter 9.3
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# popup three new window, with style
# destroy() kills one window, quit() kills all windows and app; top-level
# windows have title, icon, iconify/deiconify and protocol for wm events;
# there always is an app root window, whether by default or created as an
# explicit Tk() object; all top-level windows are containers, but never
# packed/gridded; Toplevel is like frame, but new window, and can have menu;
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from Tkinter import *
root = Tk()                                                     # explicit root
    
trees = [('The Larch!',          'light blue'),
         ('The Pine!',           'light green'),
         ('The Giant Redwood!', 'red')]
    
for (tree, color) in trees:
    win = Toplevel(root)                                        # new window
    win.title('Sing...')                                        # set border
    win.protocol('WM_