Hi There,
Sorry I am having trouble replicating this error - the demo seems to run ok for me. Is it the case that the error occurs when you click and run this link? corsi [PsychoPy] if so what operating system and browser are you using?
It looks like the code component in your version is “Auto->JS” wherar the code type in the demo is “Both” with different code typed both sides. The syntax error occurs because the python used here does not transpile automatically, so custom JS was used on the right hand side in the demo.
Thanks,
Becca