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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 bind(cls):
 """ Bind the callbacks to the buttons. """

        document["show_author_picker"].bind("click", lambda x: cls.show())

        cls.storno_btn_el.bind("click", lambda x: cls.hide())
        cls.pick_btn_el.bind("click", cls.on_pick_button_pressed)