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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 _path_polygon(self, points):
        "Low-level polygon-drawing routine."
        (xmin, ymin, xmax, ymax) = _compute_bounding_box(points)
        if invisible_p(xmax, ymax):
            return
        self.setbb(xmin, ymin)
        self.setbb(xmax, ymax)

        self.newpath()
        self.moveto(xscale(points[0][0]), yscale(points[0][1]))
        for point in points[1:]:
            self.lineto(xscale(point[0]), yscale(point[1]))
        self.closepath()