'Open a new Tkinter window that displays the entire alphabet
for the symbol font.  This is useful for constructing the
``SymbolWidget.SYMBOLS`` dictionary.'

@staticmethod
def symbolsheet(size=20):

    top = Tk()
    def destroy(e, top=top):
        top.destroy()
    top.bind('q', destroy)
    Button(top, text='Quit', command=top.destroy).pack(side='bottom')
    text = Text(top, font=('helvetica', (- size)), width=20, height=30)
    text.pack(side='left')
    sb = Scrollbar(top, command=text.yview)
    text['yscrollcommand'] = sb.set
    sb.pack(side='right', fill='y')
    text.tag_config('symbol', font=('symbol', (- size)))
    for i in range(256):
        if (i in (0, 10)):
            continue
        for (k, v) in list(SymbolWidget.SYMBOLS.items()):
            if (v == chr(i)):
                text.insert('end', ('%-10s DCTB ' % k))
                break
        else:
            text.insert('end', ('%-10d         DCTB ' % i))
        text.insert('end', ('[%s]\n' % chr(i)), 'symbol')
    top.mainloop()
