ReferenceError: deg2rad is not defined

OS (e.g. Win10): Win10
PsychoPy version (e.g. 1.84.x): 2021.2.3
Standard Standalone? (y/n) If not then what?: yes
**What are you trying to achieve?:
How can I solve the problem

It looks like you’re trying to use numpy into an online study (the error window is from an online study). That won’t work, online studies use JavaScript, not Python. I suggest starting here: PsychoPy Python to Javascript crib sheet

If you actually just need to do a degree-to-radian conversion in javascript for your study, that’s not too hard to implement: JavaScript Math: Convert an angle from degrees to radians - w3resource