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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 zoomTo(self, bbox):
        'set visible area to bbox, maintaining aspectRatio if applicable'
        self.fixPoint(self.plotviewBox.xymin, bbox.xymin)
        self.zoomlevel=max(bbox.w/self.canvasBox.w, bbox.h/self.canvasBox.h)