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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):
 """ Compute bounding box for each surface element, and then return the bounding box of all surface elements' bounding boxes. :return: A tuple of four items. These items represent western, eastern, northern and southern borders of the bounding box respectively. Values are floats in decimal degrees. """

        lons = []
        lats = []
        for surf in self.surfaces:
            west, east, north, south = surf.get_bounding_box()
            lons.extend([west, east])
            lats.extend([north, south])
        return utils.get_spherical_bounding_box(lons, lats)