code: def get_bounds(self):
          
          bounds = self._get_self_bounds()
  
          for child in self._children.values():
              child_bounds = child.get_bounds()
              bounds = [
                  [
                      none_min(bounds[0][0], child_bounds[0][0]),
                      none_min(bounds[0][1], child_bounds[0][1]),
                      ],
                  [
                      none_max(bounds[1][0], child_bounds[1][0]),
                      none_max(bounds[1][1], child_bounds[1][1]),
                      ],
                  ]
          return bounds
docs: Computes the bounds of the object and all it's children
          in the form [[lat_min, lon_min], [lat_max, lon_max]].