How about using curry for an
instant callback with parameters?


from curry import curry
    ...
    def chg_color(newcolor):
        color = newcolor

    bb = Button(root,
                text='Blue',
                command = curry(chg_color, 'blue'))

    rb = Button(root,
                text='Red',
                command = curry(chg_color, 'red'))

    ...




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