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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 do_layout(self, *args):
 """Put the bar where it's supposed to be, and size it in proportion to the size of the scrollable area. """

        if 'bar' not in self.ids:
            Clock.schedule_once(self.do_layout)
            return
        if self.orientation == 'horizontal':
            self.ids.bar.size_hint_x = self.hbar[1]
            self.ids.bar.pos_hint = {'x': self.hbar[0], 'y': 0}
        else:
            self.ids.bar.size_hint_y = self.vbar[1]
            self.ids.bar.pos_hint = {'x': 0, 'y': self.vbar[0]}
        super().do_layout(*args)