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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 _adjust_scrollbar(self, f):
 """ Adjust the scrollbar position to take into account the zooming of the figure. """

        # Adjust horizontal scrollbar :
        hb = self.horizontalScrollBar()
        hb.setValue(int(f * hb.value() + ((f - 1) * hb.pageStep()/2)))

        # Adjust the vertical scrollbar :
        vb = self.verticalScrollBar()
        vb.setValue(int(f * vb.value() + ((f - 1) * vb.pageStep()/2)))