def closed_flat(self, x, y, n):
        """Create a closed flat struture"""
        y0 = y
        for i in range(n):
            y = y0+100+i*125
            p = (x+1, y+22)
            self.columns.append(Polygon(p, 20, 85, self.space))
            p = (x+60, y+22)
            self.columns.append(Polygon(p, 20, 85, self.space))
            p = (x+30, y+70)
            self.beams.append(Polygon(p, 85, 20, self.space))
            p = (x+30, 30-y)
            self.beams.append(Polygon(p, 85, 20, self.space))
dataset/ETHPy150Open estevaofon/angry-birds-python/src/level.py/Level.closed_flat/swapped operands of `-`