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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 clipTo(self, bsp):
 """ Remove all polygons in this BSP tree that are inside the other BSP tree `bsp`. """

        self.polygons = bsp.clipPolygons(self.polygons)
        if self.front: 
            self.front.clipTo(bsp)
        if self.back: 
            self.back.clipTo(bsp)