[pstricks] almost closed c with pstricks

[mathias legrand]

Hi all,

is there a specific known manner to create example 53 (beginfig(53))
of the following webpage : 
http://zoonek.free.fr/LaTeX/Metapost/metapost.html
with pstricks. I know how to draw it with some personal tricks but I feel
there is much better.

Thank you