Pixel-width of text on a Mac

Kiri

Hello,

I got a problem presenting canvasses with respective coordinates to the canvasses presented before.
On each canvas, there is a string of which I'd need the width (in pixels) to define the x-coordinate for the following canvas.
By now, I only found a solution for Windows, for which I need an equivalent for Mac (http://stackoverflow.com/questions/32555015/how-to-get-the-visual-length-of-a-text-string-in-python).

Font is set to "mono", font size is 24.

Versions used:
OpenSesame: OpenSesame 3.1.3 Jazzy James
MacOS Sierra 10.12

Thanks a lot in advance.