How to use the flax.geometry.Blob function in flax

self.region.height, resolution=6, octaves=2)
        center = random_normal_int(
            self.region.center().x, self.region.width / 4 / 3)
        for y in self.region.range_height():
            center += (center_factory(y) - 0.5) * 3
            width = width_factory(y) * 2 + 5
            x0 = int(center - width / 2)
            x1 = int(x0 + width + 0.5)
            for x in range(x0, x1 + 1):
                self.map_canvas.set_architecture(Point(x, y), e.Water)

            left_side[y] = (Span(self.region.left, x0 - 1),)
            right_side[y] = (Span(x1 + 1, self.region.right),)
            river[y] = (Span(x0, x1),)

        return Blob(left_side), Blob(river), Blob(right_side)

def __eq__(self, other):
        if not isinstance(other, Blob):
            return NotImplemented

        return self.spans == other.spans