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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 get_bounding_box(self):
 """ Returns the bounding box of the polygons. Returns ------- out : Numpy array[2,2] or ``None`` Bounding box of this polygon in the form [[x_min, y_min], [x_max, y_max]], or ``None`` if the polygon is empty. """

        if len(self.polygons) == 0:
            return None
        return numpy.array(((min(pts[:, 0].min() for pts in self.polygons),
                             min(pts[:, 1].min() for pts in self.polygons)),
                            (max(pts[:, 0].max() for pts in self.polygons),
                             max(pts[:, 1].max() for pts in self.polygons))))