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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 process_event(self, event):
 """ Handle input on the scroll bar. :param event: the event to be processed. :returns: True if the scroll bar handled the event. """

        # Convert into absolute coordinates if needed.
        new_event = event
        if self._absolute:
            new_event.y -= self._canvas.start_line

        # Process event if needed.
        if self.is_mouse_over(new_event) and event.buttons != 0:
            self._set_pos((new_event.y - self._y) / (self._height - 1))
            return True
        return False