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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def radio_button(g, l, fn):
 """ Inheriting radio button of urwid """

    w = urwid.RadioButton(g, l, False, on_state_change=fn)
    w = urwid.AttrWrap(w, 'button normal', 'button select')
    return w