A <a href="https://en.wikipedia.org/wiki/Morin_surface" class="extiw" title="w:Morin surface">Morin surface</a> seen from "above".
AugPi
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<a href="//commons.wikimedia.org/w/index.php?title=Mathematica&amp;action=edit&amp;redlink=1" class="new" title="Mathematica (page does not exist)">Mathematica</a>