{Cartoon} on {topological prank}, part 3.

Hand-drawn by {J.Stolfi} on 2011-11-04, with a Pilot V5 ballpoint (black
0.5mm) on copier paper, actual drawing size about 11×10 + 8×6 cm; photographed
with a Kodak Playsport and cropped/composited/cleaned with Gimp.