Math. Formula to Keychain

Steps to reproduce your own:
- install Inkscape
http://www.inkscape.org/
- install textex Inkscape extension
http://pav.iki.fi/software/textext/
- install inkscape2openscad Inkscape extension
https://www.thingiverse.com/thing:25036

Then open Inkscape and select:
Extensions -> Render -> LaTeX formula...
Write your formula; the one in this keychain is:
\(x^2+(y-\sqrt[3]{x^2})^2=1\)
that is the one that draws an heart.
Then export your formula to openscad:
Extensions -> G